Kyŏnghŭng County is a kun, or county, in North Hamgyong province, North Korea. Formerly known as Ŭndŏk County (Korean: 은덕군; Hancha: 恩德郡), from 1977 to 2010.

The county borders the People's Republic of China to the northeast. Except for the southwest, it is dominated by low hills, with occasional plains. The highest point is Songjinsan, which is 1,146 m (3,760 ft). The dominant river is the Tumen, which separates the county from China. The level ground along the Tumen is developed, but approximately 80% of the county is forested.

Mining, particularly coal mining, is the chief industry in Undok, where lignite is found; Undok is the site of the Aoji Coal Mine. In addition, farming and livestock raising are widespread. The chief crops are maize, rice, soybeans, and potatoes. The Aoji-ri Chemical Complex is located in the county as well.

Undok lies on the Hambuk Line and Hoeam Line railroads.

Under Joseon period "Kyunghung", the ancient name of Undok, was one of the six post/garrisons (Korean: 육진; Hancha: 六鎭) established under the order of King Sejong the Great of Joseon in 1433, to safeguard his people from the hostile Chinese and Manchurian nomads living in Manchuria.

• Lee Gyung-Rok (Korean: 이경록; Hancha: 李慶祿) the prefect of Kyŏnghŭng (Korean: 경흥 부사; Hancha: 慶興府使)

Kyŏnghŭng County is divided into 1 town ("Ŭp") 12 villages ("Ri") and 3 worker's districts ("Rodongjagu").

• Geography of North Korea
• Administrative divisions of North Korea
• Tumen River Bridge

• Location of the four forts and the six posts
• In Korean language online encyclopedias:
  • Doosan Encyclopedia (Naver)
  • Korean language Britannica (Empas) (Map)
  • Encyclopedia of Korean Culture (Empas)
  • Pascal World Encyclopedia (Nate)