TAIPEI, September 14, 2014 (AFP) - The championship, with prize money of $90,000, was Prom's second Asian Tour victory since 2006 when he captured a title in South Korea.
"I've been waiting for this win for a long time. I am really glad I made it," he said at the Linkou International Golf and Country Club.
"Hopefully I won't have to wait another eight years to win again. I will be aiming for a third win now and try to boost my ranking on the Order of Merit."
Nicknamed the Big Dolphin due to his burly physique, Prom forced extra time when he birdied the last hole for a three-under-par 69 to tie with overnight leader Tabuena (71) in regulation play on 11-under-par 277.
After shooting matching pars on the first play-off hole, Prom needed three shots to safely find the par-five 18th green before sealing the win with a two-putt par as Tabuena narrowly missed his par putt.
Tabuena, 19, was disappointed to drop a crucial shot on 17 after bouncing back from two early bogeys with four birdies on holes nine, 12, 13 and 16 which had put him in the title mix.
"I want to thank God for keeping me calm out there. I really fought hard and gave myself a good chance to win. In the end, Prom turned out to be the better player," Tabuena said in comments supplied by the organisers.
Filipino veteran Antonio Lascuna settled for third, one shot from joining the play-off following a 69. Rookie Paul Peterson (69) of the United States, Daniel Chopra (72) of Sweden and India's Anirban Lahiri (73) finished tied for fourth on 280.
Leading scores after round 4 (par 72):
277 - Prom Meesawat (THA) 67-73-68-69, Miguel Tabuena (PHI) 73-68-65-71
278 - Antonio Lascuna (PHI) 68-69-72-69
280 - Paul Peterson (USA) 71-71-69-69, Daniel Chopra (SWE) 71-68-69-72, Anirban Lahiri (IND) 73-66-68-73
283 - Cameron Smith (AUS) 70-67-73-73
284 - Angelo Que (PHI) 68-71-76-69, Rashid Khan (IND) 71-70-72-71, Lien Lu-sen (TPE) 67-71-74-72, Yeh Wei-tze (TPE) 72-71-65-76
285 - Ryan Yip (CAN) 71-69-70-75, Thaworn Wiratchant (THA) 70-69-68-78