A motor controller used for driving a motor is provided. The motor includes a motor coil and a maximum rated current. The motor controller comprises a driving circuit, a control unit, a digital-to-analog converter, an operational amplifier, a switch circuit, and a resistor. When it is needed to decrease a settling time for the motor to reach a target position, or a vibration is detected within a camera module so as to enable an image stabilization mechanism, it is capable of temporarily supplying a driving current greater than the maximum rated current to the motor coil.