The ruling Communist Party has decided that Xiao Gang will be "dismissed" from the top position at the China Securities Regulatory Commission, the official Xinhua news agency said.
Liu Shiyu, the current head of Agricultural Bank of China - one of China's top four banks - will replace Xiao, it said.
In mid-2015, Xiao oversaw a rout on China's exchanges, with the benchmark Shanghai index plummeting by almost a third, wiping trillions of dollars from market valuations and jolting global markets.
Calls for his departure have been heard regularly since the debacle and heated up in early January after the CSRC's deployment of a "circuit breaker" closed the Shanghai and Shenzhen exchanges early twice in the four days it existed, again roiling global markets.