Debutant Srisurat, 21, set an Olympic record in the snatch with 110kg, before lifting 130kg in the clean and jerk.
Compatriot Pimsiri Sirikaew took silver (combined 232kg), with Chinese Taipei's Kuo Hsing-chun claiming bronze (231kg).
Srisurat served a two-year ban from May 2011 after testing positive for the banned anabolic steroid methandienone.
Her lift in the snatch broke the previous Olympic record of 108kg set by China's Li Xueying at London 2012.
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Thai Sukanya Srisurat lifted a combined 240kg to win Olympic weightlifting gold in the women's -58kg category three years after serving a doping ban.