Kim Sŏng-ae (born 1928) was the second wife of Kim Il-sung.
Sung-ae and Kim Il-sung became husband and wife in 1952, following the death of Il-sung's first wife in 1949, although due to the Korean War, no formal ceremony was held. One source indicates Il-sung had had an affair with her even before his first wife died. She gave birth to a daughter (Kim Kyong-jin, 1953) and two sons (Kim Pyong-il, 1955; Kim Yong-il, 1957). She later rose in political power, becoming vice-chairwoman of the Central Committee of the Korean Women's Association (조선여성총동맹) in the mid-1960s and chairwoman in the 1970s. Sung-ae held that post until resigning in 1998; since that time, little information about her has reached the outside world.
There are rumors that Sung-ae was killed in a car accident in Beijing in June 2001. Other reports claim that she's still alive (as of July 2011), though in poor health, and that Pyong-il returned to Pyongyang from his posting in Poland to visit her.