Kim Yang-gon started his political career as a vice-director of the party's International Liaison Department in 1986, and during this time he also oversaw relations with Japan as head of the DPRK-Japan Friendship Association.

His first assignment as head of relations with South Korea was a visit to Seoul in November to discuss rapprochement measures with Unification Minister Lee Jae-jeong.

At the Party Conference held in September 2010, Kim was also appointed secretary for united front and South Korea policies of the Secretariat and alternate member of the Politburo.

He visited South Korea again in October 2014 to attend the closing ceremony of the 2014 Asian Games with Hwang Pyong-so and Choe Ryong-hae, and in late August 2015 to negotiate a deal to halt military provocations around the Demilitarized Zone.

In December 2015, North Korea's news agency reported that Kim Yang-gon died in a car accident.