Strikers Le Cong Vinh, Nguyen Van Quyet and replacing Dinh Thanh Trung each scored one goal in extra time following a scoreless draw in the regular time.
The competition features national teams from Hong Kong, Singapore, Vietnam and host Myanmar.
In the first match, Vietnam overcame Hong Kong 4-3 on penalty shootout after the two teams drew 2-2 after 120 minutes while Singapore beat the host Myanmar 1-0 to reach the final.
In the earlier third-place match, Myanmar defeated Hong Kong 3-0.