He was the Chinese Ambassador to Japan from 2019 to 2023, and previously served as the Deputy Minister of Foreign Affairs from 2018 to 2019.

[2][3] In August 2017, Gong succeeded Wu Dawei as the chief representative of China in Six-party talks.

[4] He assumed the Deputy Minister of Foreign Affairs position in January 2018 until he was appointed as Ambassador to Japan.

[citation needed] According to South Korean media JoongAng Ilbo, when meeting with delegations of Korean parliamentarians, Kong expressed his regret on Korea's decision of deploying the Terminal High Altitude Area Defense (THAAD), but did not wish for Sino-Korean relations to worsen because of that.

[2] Kong is said to be close friends with the former Chinese Ambassador to the United States Cui Tiankai and former Minister of Foreign Affairs Wang Yi, as they worked together in Japan.