Australia and three-time champion Japan meet in Saturday's final.
Koo Ja-cheol scored his tournament-leading fifth goal in the 17th minute off a pass from Lee Yong-rae. Ji doubled the lead in the 28th following a feed from Koo, then made it 3-0 in the 39th with a header off Hong Jeong-ho's cross.
Alexander Geynrikh had both of Uzbekistan's goals, giving him three in the tournament. He converted a penalty kick in the 45th after defender Hwang Jae-won tangled with Olim Novkarov in the penalty area, then scored in the 53rd.
With the win, South Korea earned an automatic berth for the 2015 tournament.