He was born into a poor peasant family in Yongil County, North Kyongsang Province on April 14, Juche 16 (1927) and went to Japan in 1941.

After the liberation of Korea he worked at Onoda branch of Yamaguchi Prefecture of the Federation of Koreans in Japan as a staffer for youth affairs and at Yamaguchi and Hiroshima Prefectural headquarters of the Democratic Youth League of Koreans in Japan as a full-time cadre.

After the association was formed by President Kim Il Sung on May 25, 1955, So Man Sul held the posts of section chief at the Hiroshima Prefectural headquarters of the association, its vice-chairman and chairman and then posts of director of the organizational department of the Central Standing Committee of the association, secretary general of the association, its vice-chairman and first vice-chairman and assumed the heavy responsibility as chairman of the association in May 2001.

He was awarded many state citations including Order of Kim Il Sung, Order of Kim Jong Il, the title of labor hero of the DPRK and the National Reunification Prize.

The Central Standing Committee of the association issued an obituary of him on Feb. 20.

It said that So remained boundlessly loyal to Kim Il Sung and Kim Jong Il till the last moments of his life and devoted himself to the patriotic work to usher in a new heyday of the association under the leadership of the dear respected Kim Jong Un and achieve the prosperity of the socialist homeland and national reunification.

The precious feats performed by him in the work of the association and the movement of Koreans in Japan will shine forever, it added.