Chatichai Choonhavan (Thai: ชาติชาย ชุณหะวัณ; rtgs: Chatchai Chunhawan, 5 April 1920 — 6 May 1998) was a Thai army officer, diplomat and politician. From 1986 to 1991, he was the chairman of the Thai Nation Party and served as the Prime Minister of Thailand from August 1988 until the coup d'état of February 1991.