The month-long operation by police from China, Thailand, Myanmar and Laos led to the arrest of 812 suspects from the four nations and Vietnam, Xinhua news agency quoted Chinese police as saying.
Police recovered 1.93 tonnes of drugs as well as guns and ammunition in the operations that are scheduled to continue for another month, spokesman Lan Weihong said.
Speaking at the headquarters for the joint operation in China's south-western city of Kunming, Lan said police intelligence suggested that several drug rings had "ceased operation in the wake of the crackdown," the agency reported.
Police are targeting large-scale trafficking and drug production bases in the notorious "Golden Triangle" straddling the borders between the four countries.
The agreement to cooperate on the joint mission came following the murder of 13 Chinese sailors on the Mekong River in October 2011.
Alleged Golden Triangle drug lord Nor Kham and three accomplices were executed for the murders.