A motor actuator may include a motor, a cam driven by the motor, switch contact pieces operated by the cam, a housing case which accommodates at least the cam, the switch contact pieces, and connection terminals attached to the housing case for connecting an external power supply to the motor. The cam is formed with a step part for operating the switch contact pieces and the switch contact pieces are structured as a position sensor. The connection terminals may include a first switch terminal, a second switch terminal, a first motor terminal, and a second motor terminal. The housing case is formed with at least three cut-out portions so that the first switch terminal, the first motor terminal and the second switch terminal are disposed in this order.