Around 70 people fell into the water when the two passenger boats overturned on a river in Qianxi city, Guizhou province, Xinhua news agency said citing local authorities.
Rescue workers were searching for 14 people still missing on Sunday evening.
China’s leader Xi Jinping urged “all-out efforts” in the search and rescue operations and treatment of those injured, Xinhua said.
Sunday’s incident comes just over two months after eleven people were killed in a boat collision in central China.
The collision in Hunan province occurred when a passenger boat struck an industrial vessel, throwing 19 people overboard.
Chinese President Xi Jinping on Sunday urged all-out efforts to search those falling into water and treat the injured after two boats capsized in southwest China’s Guizhou Province.