Rungroj lost to Peter Rosenmeier of Denmark 8-11, 7-11, 13-11, 5-11 in the semifinal of the men’s singles Class 6.
This was Rungroj's second consecutive bronze at the Paralympics.
Rungroj had won the gold at the 2012 Paralympics and a bronze at the 2016 Paralympics.
Rosenmeier, ranked second in the world, had won the bronze in the 2016 Paralympics.
“I would like to apologise to fans that I could not get the gold medal. I have to play in men’s Team Class 6-7. I would like everyone to keep cheering for the Thai Paralympics team. In the next three years, I still want to play at the Paris 2024 Paralympic Games and win more medals for Thailand,” Rungroj said.