The Vietnamese side played a counter-attacking style and created a number of chances in the first half, but none were converted into goals.
Myanmar however managed to secure the opener just four minutes after the interval.
After changes were made to the Vietnamese squad, Khac Khiem received a ball from the right wing and headed it into the net.
In a later match on December 12, Vietnam’s U21 team lost 0-1 to Thailand. The only goal of the match was by Settawur Wongsai in the 43rd minute.
The annual tournament will run in the southern province of Can Tho from December 12-22.
Five teams compete in a round robin format, with the two best teams entering the final. The winner will walk away with VND700 million (US$30,000).
