Kayah State (Burmese: ကယားျပည္နယ္, pronounced: [kəjá pjìnɛ̀] formerly, Karenni State) is a state of Myanmar. Situated in eastern Myanmar, it is bounded on the north by Shan State, on the east by Thailand's Mae Hong Son Province, and on the south and west by Kayin State. It lies approximately between 18° 30' and 19° 55' north latitude and between 94°40' and 97° 93' east longitude. The area is 11,670 km² (4,510 sq mi). Its capital is Loikaw (also spelt Loi-kaw). The estimated population in 1998 was approximately 207,357, according to UNICEF. It is inhabited primarily by the Karenni ethnic group, also known as Red Karen or Kayah, a Sino-Tibetan people.

Karenni ( Kayah )State is located in the eastern part of Myanmar. The relief of Karenni ( Kayah ) State is mountainous with the Dawna Range and the Karen Hills also known as "Karenni-Karen" mountains separated by the Salween River as it flows through Karenni ( Kayah ) State. Balu Chaung, flows from Inle Lake flow to Than Lwin River and converge with the Salween in southern Karenni (Kayah) State.

Lawpita Dam, built in 1950 as a bilateral reparation agreement with Japan, is a major hydroelectric production dam which produces a quarter of the total hydroelectric power generation in Myanmar.

Karenni States is the name formerly given to a group of states that included Kantarawadi, Kyebogyi and Bawlake. These states were located south of the Federated Shan States and east of British Burma. According to the 1930 census, the states had a total population of 58,761 with Kantarawadi (3,161 square miles or 8,190 square kilometres), 30,677, Kyebogyi (790 square miles or 2,000 square kilometres), 14,282 and Bawlake (568 square miles or 1,470 square kilometres), 13,802.

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