Leitrim–Sligo was a parliamentary constituency represented in Dáil Éireann, the lower house of the Irish parliament or Oireachtas from 1923 to 1937. The constituency elected 7 deputies (Teachtaí Dála, commonly known as TDs) to the Dáil, on the system of proportional representation by means of the single transferable vote (PR-STV).

The constituency was defined in the Electoral Act 1923 as:^[1]

"The administrative counties of Leitrim and Sligo."

This was the first time that the Dáil had not used constituencies defined under British law. Leitrim–Sligo replaced the old Leitrim–Roscommon North and Sligo–Mayo East constituencies, which had been created under the Government of Ireland Act 1920. The constituency was first used at the 1923 general election.^[1]

Under the Electoral (Revision of Constituencies) Act 1935, the Leitrim–Sligo constituency was abolished, and replaced for the 1937 general election by two separate 3 seat constituencies: Sligo and Leitrim.^[2] The territory was reunited as Sligo–Leitrim under the Electoral (Amendment) Act 1947, in operation from the 1948 general election.^[3] The Sligo–Leitrim constituency was abolished at the 2007 general election,^[4][5] and replaced by two new constituencies: Roscommon–South Leitrim and Sligo–North Leitrim.

Note: The columns in this table are used only for presentational purposes, and no significance should be attached to the order of columns. For details of the order in which seats were won at each election, see the detailed results of that election.

• Politics of the Republic of Ireland
• Historic Dáil constituencies
• Elections in the Republic of Ireland