Gan was born in 1915 in Jianchang County, Liaoning. In his youth, he participated in revolutionary activities and joined the Chinese Communist Party in 1936. During the later years of the Chinese Civil War, he worked in Beijing within government organs related to internal affairs.[2]
After the founding of the People's Republic of China in 1949, Gan held a series of positions in the central government. He served as deputy director and later director of the General Office of the Ministry of Internal Affairs of the Central People's Government of the People's Republic of China, and was a member of the ministry's Party leadership group as well as secretary. He subsequently became secretary-general and executive deputy director of the Internal Affairs Office of the State Council of the People's Republic of China, and also served as deputy secretary of the Party committee of central political and legal organs.[3]
During the Cultural Revolution, Gan opposed the policies and actions associated with Lin Biao and the Gang of Four. After the end of the Cultural Revolution and the arrest of the Gang of Four, he was appointed deputy secretary-general of the Chinese Academy of Sciences, serving in that capacity between August 1977 and 1978.[4]
In 1981, Gan participated in the preparations for the re-establishment of the China Law Society. At the society's first national congress after its restoration in 1982, he was elected vice president and became a member of its leading Party group.[5] Following his retirement in 1986, he served as an adviser to the society and initiated the publication of the China Law Yearbook, acting as its editor-in-chief.[6] He contributed to discussions on legal theory in the context of the reform and opening up. Gan died of illness in Beijing on December 4, 1992, at the age of 77.[7]