A blower fan including a motor having a rotating shaft, a bracket, a fan housing having a cavity, a fan wheel, and fan blades. The motor is disposed on the fan housing via the bracket. An extended portion of the rotating shaft extends into the cavity of the fan housing and connects with the fan wheel. The fan blades are disposed on the rotating shaft and between the motor and the fan housing. On the casing of the motor is disposed with air vents. The bracket forms an annular side wall. A cavity is formed inside the annular side wall. The annular side wall is outfitted with air outlets which are connected with the cavity of the annular side wall and the fan blades are disposed in the cavity.