Staging a defensive line-up, Myanmar created fewer chances but scored more goals than their rival Vietnam, whose players wasted so many clear chances during the game.
Myanmar opened the score in the 38th minute from the penalty shot.
From a free kick some 20 meters from the Vietnamese goal, Myanmar curved the ball into the box and the ball came to the left hand of Ngoc Thang standing in fence to protect the goal.
Myanmar was awarded a penalty and midfielder Aung Si Thu converted it into the opening goal for Myanmar.
The goal was scored during the first attack of Myanmar in the first half despite Vietnam staged an attacking formation and has created relentless assaults during the first minutes of the game.
At the 71st minute, Vietnamese midfielder Huy Toan leveled 1-1 following an attack on the left side.
Striker Mac Hong Quan blasted a close range shot but was stopped by Myanmar’s keeper Phyo Kyaw Zin. The loose ball came to Huy Toan to cushion home a goal to level the match.
Five minutes later, defender Nay Lin of Myanmar lifted the result to 2-1 thanks to a shot from the right side. The flying ball touched Vietnamese defender Thanh Hien and changed direction to go into the net.
Striker Mac Hong Quan today missed at least three chances to score for Vietnam.
Myanmar entered the semis as group A winner with three win, 4-2 over Indonesia, 2-1 over Singapore, 5-1 over the Philippines; and a 3-3 draw with Cambodia.
Vietnam ranked second in group B after defeating Brunei 6-0, Malaysia 5-1, Laos 1-0, and Timor Leste 4-0, but losing 1-3 to Thailand.
The other semifinal match between Thailand and Indonesia will take place today, at 7:30pm.
What the stars mean:
★ Poor ★ ★ Promising ★★★ Good ★★★★ Very good ★★★★★ Exceptional