Ji started out in the leaders' pack and then jostled with defending champion Mubarak Hassan Shami of Qatar at the 33-kilometer point in this 42.195km race.
Ji extended his lead with about 8km left and wasn't threatened over the last 5km. Japan's Yukihiro Kitaoka was second at 2:12:46, and Shami fell to third at 2:12:53.
South Korea has now won five men's marathon titles at the Asian Games.
ShareThis