The invention discloses a chemical reaction tank. The chemical reaction tank comprises a reaction tank main body, a side of the reaction tank main body is provided with a gas-liquid outlet, the gas-liquid outlet is connected to the reaction tank main body, the top and the bottom of the reaction tank main body are respectively connected to a top cover and a bottom cover, the top cover and the bottom cover are respectively and detachably connected to the reaction tank main body, the part of the reaction tank main body close to the top is provided with a heating jacket, the heating jacket is fixed to the reaction tank main body, a stirring pipe is arranged in the heating jacket, the top of the stirring pipe goes through the heating jacket and is connected to a heater, a heating pipe is arranged in the stirring pipe, and the heating pipe is electrically connected to the heater. The chemical reaction tank has a compact reaction tank structure, less mechanical transmission, a long service life and high safety, is convenient for use and maintenance, prevents reaction solution outflow, realizes full mixing of the reaction solution in flowing, can carry out heating according to cases, improves a reaction rate, realizes a vacuum reaction and further improves reaction solution full-reaction performances.