'I'm really happy,' Thaworn said. 'Everything worked in my favor in the final round.'
Thaworn finished at 18-under 270, one stroke ahead of compatriot Chapchai Nirat (67). Third-round leader Scott Strange (70) finished three shots back in a tie for third with fellow Australian Terry Pilkadaris (68) and Taiwan's Lu Wei-lan (67).
Strange, chasing his second title of the year, bogeyed the par-5 12th and 14th holes to fall out of contention.