House of Representatives (Japan)

The House of Representatives (衆議院, Shūgiin) is the lower house of the National Diet of Japan. The House of Councillors is the upper house.

House of Representatives


The 48th House of Representatives
Tadamori Oshima, LDP
since April 21, 2015
Hirotaka Akamatsu, CDP
since November 1, 2017
Yoshihide Suga, LDP
since September 16, 2020
Yukio Edano, CDP
since October 23, 2017
Political groups
Government (307)
  •   LDP (278)
  •   Kōmeitō (29)

Opposition (158)

Parallel voting:
First past the post (289 seats)
Party-list proportional representation (176 seats)
Last election
October 22, 2017
Next election
On or before October 22, 2021
Meeting place
Chamber of the House of Representatives

The composition of the House is established by Article 41 [ja] and Article 42 [ja] of the Constitution of Japan.[1] The House of Representatives has 465 members, elected for a four-year term. Of these, 176 members are elected from 11 multi-member constituencies by a party-list system of proportional representation, and 289 are elected from single-member constituencies. 233 seats are required for a majority.

The overall voting system used to elect the House of Representatives is a parallel system, a form of semi-proportional representation. Under a parallel system the allocation of list seats does not take into account the outcome in the single seat constituencies. Therefore, the overall allocation of seats in the House of Representatives is not proportional, to the advantage of larger parties. In contrast, in bodies such as the German Bundestag or the Scottish Parliament the election of single-seat members and party list members is linked, so that the overall result respects proportional representation fully or to some degree.[citation needed]

The House of Representatives is the more powerful of the two houses, able to override vetoes on bills imposed by the House of Councillors with a two-thirds majority. The house is currently led by Prime Minister Yoshihide Suga.[2][3][4]

Right to vote and candidature

  • Japanese nationals aged 18 years and older may vote (prior to 2016, the voting age was 20).[5]
  • Japanese nationals aged 25 years and older may run for office in the lower house.

Differences between the Upper and Lower Houses

The House of Representatives has several powers not given to the House of Councillors. If a bill is passed by the lower house (the House of Representatives) but is voted down by the upper house (the House of Councillors) the House of Representatives can override the decision of the House of Councillors by a two-thirds vote in the affirmative. However, in the case of treaties, the budget, and the selection of the prime minister, the House of Councillors can only delay passage, but not block the legislation. As a result, the House of Representatives is considered the more powerful house.

Members of the House of Representatives, who are elected to a maximum of four years, sit for a shorter term than members of the House of Councillors, who are elected to full six-year terms. The lower house can also be dissolved by the Prime Minister or the passage of a nonconfidence motion, while the House of Councillors cannot be dissolved. Thus the House of Representatives is considered to be more sensitive to public opinion, and is termed the "lower house".

While the legislative term is nominally 4 years, early elections for the lower house are very common, and the median lifespan of postwar legislatures has in practice been around 3 years.

Current composition

Composition of the House of Representatives of Japan (as of 3 June 2021 during the 204th National Diet)[6]
In-House Groups
[innai] kaiha
Parties Representatives
Liberal Democratic Party
Jiyūminshutō / Mushozoku no Kai
Liberal Democratic Party/Association of Independents
LDP, Independents 277
The Constitutional Democratic Party of Japan and the Independent
Rikken Minshutō・Mushozoku
Constitutional Democratic Party/Independents
CDP, SDP, independents 114
Kōmeitō 29
Japanese Communist Party
Nihon Kyōsantō
JCP 12
Nippon Ishin (Japan Innovation Party)
Nippon Ishin no Kai・Mushozoku no Kai
Nippon Ishin no Kai/Association of Independents
Ishin, Independent 11
  Democratic Party For the People
Kokumin MinshutōMushozoku Kurabu
Democratic Party for the People/Independents Club
DPFP, Independents 10
Members not affiliated with a parliamentary group/non-inscrits
LDP (Speaker), CDP (Vice-Speaker), N-Koku, independents 10
Vacant: Tokyo 9, Hiroshima 3 (no more by-elections before the 2021 general House of Representatives election)[7] 2
Total 465

For a list of majoritarian members and proportional members from Hokkaidō, see the List of members of the Diet of Japan.

Latest election result

Liberal Democratic Party 18,555,71733.286626,500,77747.82218284–7
Constitutional Democratic Party of Japan11,084,89019.88374,726,3268.531855New
Kibō no Tō9,677,52417.363211,437,60220.641850New
Japanese Communist Party4,404,0817.90114,998,9329.02112–9
Nippon Ishin no Kai3,387,0976.0781,765,0533.18311New
Social Democratic Party 941,3241.691634,7701.15120
Happiness Realization Party292,0840.520159,1710.29000
New Party Daichi226,5520.4100New
Shiji Seitō Nashi125,0190.22000
Party for Japanese Kokoro85,5520.1500–2
Assembly for Zero Parliamentary Compensation21,8920.0400New
New Party Constitution Article 96,6550.0100New
Fair Party5,5180.0100New
Japan New Party5,2910.0100New
Assembly to Make Nagano Prefecture the Best Economy in Japan3,7840.0100New
Workers Party Aiming for Liberation of Labor3,1330.0100New
Association to Innovate Metropolitan Government2,9310.0100New
Katsuko Inumaru and Republican Party1,5700.00000
World Economic Community Party1,3070.00000
Valid votes55,757,55297.9155,422,08897.32
Invalid/blank votes1,187,7022.091,528,8692.68
Total votes56,945,254100.0056,950,957100.00
Registered voters/turnout106,091,22953.68106,091,22953.68
Source: Ministry of Internal Affairs and Communications

Election results for major parties since 1958


  • green: Ruling party/coalition before and after the lower house election
  • red: Ruling party/coalition until the election = Change of government as a result of the lower house election
  • blue: Ruling party/coalition after the election = Change of government as a result of the lower house election
  • none: Opposition before and after the election

Note that the composition of the ruling coalition may change between lower house elections, e.g. after upper house elections. Parties who vote with the government in the Diet, but are not part of the cabinet (e.g. SDP & NPH after the 1996 election) are not shaded.

Parallel electoral system (since 1996)

Vote and seats by party and segment
Parties Segment 1996[8]2000[9]2003[10]2005[11]2009[12]201220142017
Total seats500480480480480480475465
Liberal Democratic Party (LDP) Jiyū MinshutōFPTP 38.6%41.0%43.9%47.8%38.6%43.0%48.1%48.21%
PR 32.8%28.3%35.0%38.1%26.7%27.6%33.1%33.28%
Total seats239233237296119294291284
Constitutional Democratic Party (CDP) Rikken MinshutōFPTP 8.75%
PR 19.88%
Total seats55
Party of Hope Kibō no TōFPTP 20.64%
PR 17.36%
Total seats50
Democratic Party of Japan (DPJ) Minshutō (1996–2014)
Democratic Party (DP) Minshintō (2017)
FPTP 10.6%27.6%36.7%36.4%47.4%22.8%22.5%no party
≈14 members
PR 16.1%25.2%37.4%31.0%42.4%15.9%18.3%
Total seats521271771133085773
Japan Restoration Party (JRP) Nippon Ishin no Kai (2012)
Japan Innovation Party (JIP) Ishin no Tō (2014)
FPTP 11.6%8.2%3.18%
PR 20.3%15.7%6.07%
Total seats544111
(New) Komeito (K/NK/NKP/CGP/NCGP/etc.) KōmeitōFPTP 2.0%1.5%1.4%1.1%1.4%1.5%1.5%
PR 13.0%14.8%13.3%11.4%11.8%13.7%12.51%
Total seats 31343121313529
Japanese Communist Party (JCP) Nihon KyōsantōFPTP 12.6%12.1%8.1%7.2%4.2%7.8%13.3%9.02%
PR 13.1%11.2%7.8%7.2%7.0%6.1%11.4%7.9%
Total seats262099982112
Social Democratic Party (SDP) Shakai MinshutōFPTP 2.2%3.8%2.9%1.5%1.9%0.7%0.8%1.15%
PR 6.4%9.4%5.1%5.5%4.2%2.3%2.5%1.69%
Total seats1519677222
New Frontier Party (NFP) Shinshintō (1996)
Liberal Party Jiyūtō (2000)
Tomorrow Party of Japan (TPJ) Nippon Mirai no Tō (2012)
People's Life Party (PLP) Seikatsu no Tō (2014)
Liberal Party (LP) Jiyūtō (2017)
FPTP 28.0%3.4%5.0%1.0%no party
2 members
PR 28.0%11.0%5.7%1.9%
Total seats1562292
Your Party (YP) Minna no TōFPTP 0.8%4.7%
PR 4.2%8.7%
Total seats519
Conservative Party Hoshutō (2000)
New Conservative Party Hoshu Shintō (2003)
FPTP 2.0%1.3%
PR 0.4%
Total seats74
New Party Harbinger (NPH) Shintō SakigakeFPTP 1.3%
PR 1.0%
Total seats2

SNTV multi-member districts (1947–1993)

Vote for candidates by party and
seats by party
Parties 1958[14]1960[14]1963[14]1967[14]1969[14]1972[14]1976[14]1979[14]1980[14]1983[14]1986[14]1990[14]1993[14]
Total seats467467467486486491511511511511512512511
Liberal Democratic Party (LDP) Jiyū Minshutō 57.8%57.6%54.7%48.8%47.6%46.8%41.8%44.6%47.9%48.9%49.4%46.1%36.7%
Japan Socialist Party (JSP) Nihon Shakaitō 32.9%27.6%29.0%27.9%21.4%21.9%20.7%19.7%19.3%19.5%17.2%24.4%15.4%
Japan Renewal Party (JRP) Shinseitō 10.1%
Kōmeitō (K/KP/CGP/etc.) Kōmeitō 5.4%10.9%8.5%11.0%9.8%9.0%10.1%9.4%8.0%8.1%
Japan New Party (JNP) Nihon Shintō 8.0%
Democratic Socialist Party (DSP) Minshatō 8.8%7.4%7.4%7.7%7.0%6.3%6.8%6.6%7.3%6.4%4.8%3.5%
Japanese Communist Party (JCP) Nihon Kyōsantō 2.6%2.9%4.0%4.8%6.8%10.5%10.4%10.4%9.8%9.3%8.8%8.0%7.7%
New Party Harbinger (NPH) Shintō Sakigake 3.5%


Meiji period (1890-1912)

Kuroda Kiyotaka, Satsuma samurai and prime minister in the late 1880s, coined the term "transcendentalism" (超然主義, chōzen shugi) on the occasion of the promulgation of the Meiji Constitution in 1889. The oligarchs should try to "transcend" electoral politics and govern without partisan majorities the House of Representatives
Itō Hirobumi, a Chōshū samurai, member of the House of Peers and prime minister of Japan on three non-consecutive occasions between 1885 and 1901. He was a main architect of the Imperial Constitution which created the Imperial Diet. When the oligarchs attempts to govern "transcendentally" mostly failed in the 1890s, he saw the necessity for permanent allies among elected political parties.
Hara Takashi, although actually himself born a Morioka noble, made his career as commoner-politician and became the first and one of only three prime ministers from the House of Representatives in the Empire

The Japanese parliament, then known as the Imperial Diet, was established in 1890 as a result of the 1889 Meiji Constitution. It was modeled on the parliaments of several Western countries, particularly the German Empire and the United Kingdom, because of the Emperor Meiji's westernizing reforms. The Imperial Diet consisted of two chambers, the elected House of Representatives which was the lower house, and the House of Peers which was the upper house. This format was similar to the House of Lords in the Westminster system, or the Herrenhaus in Prussia, where the upper house represented the aristocracy.

Both houses, and also the Emperor, had to agree on legislation, and even at the height of party-based constitutional government, the House of Peers could simply vote down bills deemed too liberal by the Meiji oligarchy, such as the introduction of women's suffrage, increases in local autonomy, or trade union rights. The prime minister and his government served at the Emperor's pleasure, and could not be removed by the Imperial Diet. However, the right to vote on, and if necessary to block, legislation including the budget, gave the House of Representatives leverage to force the government into negotiations. After an early period of frequent confrontation and temporary alliances between the cabinet and political parties in the lower house, parts of the Meiji oligarchy more sympathetic to political parties around Itō Hirobumi and parts of the liberal parties eventually formed a more permanent alliance, in the form of the Rikken Seiyūkai in 1900. The confidence of the House of Representatives was never a formal requirement to govern, but between 1905 and 1918, only one cabinet took office that did not enjoy majority support in the House of Representatives.[15]

Taisho and early Showa periods (1912-1937)

During the Taishō political crisis in 1913, a no-confidence vote[16] against the third Katsura government, accompanied by major demonstrations outside the Diet, was followed shortly by resignation. Subsequently, in the period often referred to as Taishō democracy, it became increasingly customary to appoint many ministers, including several prime ministers, from the House of Representatives – Hara Takashi was the first commoner to become prime minister in 1918.

In the same year, the Rice Riots had confronted the government with an unprecedented scale of domestic unrest, and a German Revolution brought the Prusso-German monarchy to an end, the very system Meiji oligarchs had used as the main model for the Meiji constitution to consolidate and preserve Imperial power. Even Yamagata Aritomo and other oligarchs that had been fundamentally opposed to political parties, became more inclined to cooperate with the still mainly bourgeoisie parties, to prevent a rise of socialism or other movements that might threaten Imperial rule. Socialist parties would not be represented in significant numbers in the lower house until the 1930s.

The initially very high census suffrage requirement was reduced several times, until the introduction of universal male suffrage in 1925. The electoral system to the House of Representatives was also fundamentally changed several times: between systems of "small" mostly single- and few multi-member electoral districts (1890s, 1920, 1924), "medium" mostly multi-member districts (1928–1942) and "large" electoral districts (usually only one, rarely two city and one counties district per prefecture; 1900s and 1910s), using first-past-the-post in single-member districts, plurality-at-large voting (1890s) or single non-transferable vote in the multi-member districts.

Influence of the House of Representatives on the government increased, and the party cabinets of the 1920s brought Japan apparently closer to a parliamentary system of government, and there were several reforms to the upper house in 1925. However, the balance of powers between the two houses and the influential role of extra-constitutional actors such as the Genrō (who still selected the prime minister) or the military (that had brought down several cabinets) remained in essence untouched. Within a year of the Japanese invasion of Manchuria in September 1931, a series of assassinations and coup attempts followed. Party governments were replaced by governments of "national unity" (kyokoku itchi) which were dominated by nobles, bureaucrats and increasingly the military.

World War II and aftermath (1937-1947)

After the Marco Polo Bridge Incident and the start of war in 1937, the influence of the Imperial Diet was further diminished, though never fully eliminated, by special laws such as the National Mobilization Law and expanded powers for cabinet agencies such as the Planning Board.[17] The House of Representatives in the Empire had a four-year term and could be dissolved by the Emperor. In contrast, members of the House of Peers had either life tenure (subject to revocation by the Emperor) or a seven-year term in the case of members elected in mutual peerage elections among the three lower peerage ranks, top taxpayer and academic peerage elections. During the war, the term of the members of the House of Representatives elected in the last pre-war election of 1937 was extended by one year.

In the 1946 election to the House of Representatives, held under the U.S.-led Allied occupation of Japan, women's suffrage was introduced, and a system of "large" electoral districts (one or two per prefecture) with limited voting was used. A change in the electoral law in April 1945 had for the first time allocated 30 seats to the established colonies of the Empire: Karafuto (Sakhalin), Taiwan, and Chōsen (Korea); but this change was never implemented. Similarly, Korea and Taiwan were granted several appointed members of the House of Peers in 1945.

In 1946, both houses of the Imperial Diet (together with the Emperor) passed the postwar constitution which took effect in 1947. The Imperial Diet was renamed the National Diet, the House of Peers was replaced by an elected upper house called the House of Councillors, and the House of Representatives would now be able to override the upper house in important matters. The constitution also gave the Diet exclusive legislative authority, without involvement of the Emperor, and explicitly made the cabinet responsible to the Diet and requires that the prime minister has the support of a majority in the House of Representatives.

Late Showa period (1947-1989)

Shigeru Yoshida, prime minister 1946-1947 as a member of the House of Peers and 1948-1954 as a member of the House of Representatives, oversaw the end of the American-led occupation and the beginning of the Japanese economic miracle.

The Diet first met under the new constitution on 20 May 1947.[18] Four days later, Tetsu Katayama of the Democratic Socialist Party became Japan's first socialist prime minister and the first since the introduction of parliamentarianism.

Since the end of US rule in 1952, it has been the norm that the prime minister dissolves the House of Representatives before its 4-year term expires. Only once, in 1976, did the House last a full 4 years. It has become tradition to give nicknames to each dissolution, usually referencing a major political issue or controversy. One infamous example was on 14 March 1953, when Shigeru Yoshida dissolved the House and called for new election, after he resorted to name calling people during a meeting of the budget committee. This came to be known as the "you idiot" dissolution.[19]

Recent history (since 1989)

Members (since 1990)

See also


  1. "The Constitution of Japan". Japanese Law Translation. Retrieved August 7, 2020.
  5. "Diet enacts law lowering voting age to 18 from 20". The Japan Times.
  6. House of Representatives: 会派名及び会派別所属議員数 (Names and number of members of kaiha/parliamentary groups/caucuses) (Japanese), Strength of the In-House Groups in the House of Representatives (English), retrieved June 5, 2021.
  7. Sankei Shimbun, April 1, 2021: 衆院、河井被告の辞職を許可, retrieved May 8, 2021.
  8. Ministry of Internal Affairs and Communications (MIC/Sōmushō): 第41回衆議院議員総選挙結果
  9. MIC: 第42回衆議院議員総選挙結果
  10. MIC: 衆議院議員総選挙・最高裁判所裁判官国民審査結果調
  11. MIC: 平成17年9月11日執行 衆議院議員総選挙・最高裁判所裁判官国民審査結果調
  12. MIC: 平成21年8月30日執行 衆議院議員総選挙・最高裁判所裁判官国民審査結果調
  13. Includes Takahiro Inoue (independent, Fukuoka 1st district) who was retroactively nominated as LDP candidate; Reuters, December 14, 2014: 自民、井上氏を追加公認 Archived December 17, 2014, at
  14. Ministry of Internal Affairs and Communications, statistics bureau: 衆議院議員総選挙の党派別当選者数及び得票数(昭和33年~平成5年)
  15. Cambridge History of Japan, Vol. 6, p. 35
  16. Wikisource: 第三次桂内閣に対する内閣不信任上奏決議案提出及び趣旨説明, excerpt from the Imperial Diet minutes, House of Representatives session February 5, 1913
  17. The Cambridge History of Japan, Vol.6, chapters 2 (Taichirō Mitani: The establishment of party cabinets, 1889–1932) and 3 (Gordon M. Berger: Politics and mobilization in Japan, 1931–1945).
  18. National Parliaments: Japan - Library of Congress
  19. Dissolving the House of Representatives: A Powerful Political Tool -