In the 18th and final hole he scored a par to defeat Filipino Lloyd Jefferson Go who finished second.
Chen got off to a bad start and kept making bogeys, but he got back on track with three birdies on holes 15, 17, and 18. When he and Go (-8) had the same number of strokes, they had to play off on the 18th hole. Go was unlucky and hit the ball into the water, so Chen won the championship with a par.
Chen had entered the event, part of the Asian Development Tour (ADT), ranked 403rd in the world, but took home a trophy and prize money of US$13,125.
The tournament was played at the BRG Da Nang Golf Resort, a course designed by golf legend Jack Nicklaus with 18 holes and a standard par of 72.
The tournament attracted 115 golfers, including 40 from Vietnam.
Only five of the local players made the cut of +7 after the first two rounds to advance to the final round.
Doan Van Dinh and Nguyen Huu Quyet finished the event with +10 over par, the best result in the domestic group.
The event had prize money of $75,000.