The utility model discloses a ventilating fan used in toilet, which is composed of a shell, a frame, an electric motor which is fixed in the shell through the frame and fan blades arranged on output shaft of the electric motor. The utility model is characterized in that the shell is provided with at least one air guide hole. A sealing cover plate is arranged on one side of the shell which is close to the toilet. The air guide hole is directly connected with the exhaust tubes of toilet wares so as to discharge air in the toilet from top to bottom, extract smell generated by the toilet wares. The utility model with good air extracting effect purifies air in the toilet completely.