Thailand also got two more bronze medals from wheelchair racer Saichon Konjen and taekwondo star Khwansuda Phuangkitcha as the sport made its Paralympic debut.
In the final days before Sunday’s closing ceremony, the 24-year-old Pongsakorn won his third gold of the COVID-delayed tournament and fourth for Thailand as he retained his 800m T53 title with a new Paralympic record time of 1:36.07.
World record holder Canada’s Brent Lakatos, who lost to Pongsakorn for the third successive event, came second in 1:36.32. Pierre Fairbank of France was third in 1:39.67.
Pongsakorn also won the 400m T53, successfully retaining his Rio crown, and 100m T53 events.
Saichon finished third in the 800m T54 event, clocking 1:34.19. Marcel Hug of Switzerland won gold in 1:33.68 while China’s Dai Yunqiang took silver in 1:34.11.
Thailand have so far won four gold medals - all in wheelchair racing - with Athiwat Paeng-Nuea claiming the 100m T54 title.
Pongsakorn will get B21.6mn in reward from the government for winning three gold medals.
Under the National Sports Development Fund’s bonus scheme for Paralympians, a champion will get B7.2mn, a silver winner B4.8mn, and a bronze medallist B3mn.