Belarus shot-putter Nadzeya Ostapchuk, who was a bronze medallist in Beijing, had tested positive for the steroid turinabol.
The International Olympic Committee (IOC) has stripped the three of their gold medals, won in Beijing in 2008.
China faces a one-year ban from worldwide weightlifting, which should be triggered for having three Olympic doping disqualifications in a retesting program by the IOC, which announced the verdicts on Thursday.
China faces a one-year ban from global weightlifting competitions after three of its athletes were stripped of their 2008 Olympic gold medals on Thursday following re-tests of samples from the Beijing Games.
She had only been promoted to bronze medal position after compatriot Natallia Mikhnevich failed an earlier dope test.
Liu was also a gold medalist at the 2004 Athens Olympics in the 69kg class, Cao took two gold at the 2006 and 2007 World Weightlifting Championships, while Chen took three golds at the 2007 World Weightlifting Championships.
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Doping retests from the 2008 and 2012 Olympic Games resulted in numerous positive results.
"In line with the relevant rules and regulations, the IWF imposed mandatory provisional suspension upon the athlete, who remains provisionally suspended in view of a potential anti-doping rule violation until the case is closed", said the IWF statement.
Due to the similarity of the Chinese athletes' three cases, the IOC is recommending the International Weightlifting Federation (IWF) investigate the Chinese team more thoroughly.
Four athletes have been disqualified from the London 2012 Olympics: Turkish weightlifter Sibel Simsek, Azerbaijani lifter Intigam Zairov and Armenian Norayr Vardanyan.
Weightlifting, athletics, cycling, swimming and wrestling have all been affected by the re-tests.