Ms Pimsiri,22, achieved her second place silver medal with total of 236kg, comprising 100kg in the snatch lift and 136kg in the clean and jerk, 10kg behind China’s Li Xueying who snatched an Olympic record of 108kg and jerked up 138kg for an Olympic record total of 246kg.
Yuliya Kalina of Ukraine placed third with 235kg.
Another Thai woman, Rattikan Gulnoi, missed the bronze but ranked fourth place with 100kg in the snatch and 134kg clean and jerk, totalling 234kg.
Two Thai women weightlifters were earlier unable to win medals in the women's 48-kilogramme event on Saturday after Sirivimon Pramongkhol finished only in fourth place.
Meanwhile Panida Khamsri, a medal favourite, bombed out after three failed snatch attempts at 81kg.