An electric bike having an improved effect of heat dissipation has a body, a driving device, and a battery. The body has a frame, a rear wheel, and a front wheel, wherein the rear wheel and the front wheel are mounted to the frame. The driving device is mounted to the body and has a motor and a shell. The motor is connected with the frame and has a front end near the front wheel and a rear end near the rear wheel. The shell covers the motor and has multiple inlets and multiple outlets disposed therethrough. The multiple inlets are located near the front end of the motor. The multiple outlets are located near the rear end of the motor. The battery is electrically connected to the motor. The front wheel, the battery, the motor, and the rear wheel are serially aligned.