Assembly work of an electric motor in which a power supply device and a rotation detector both equipped in a motor case are connected to a control device via a connector unit can be made easy. A power window motor includes an armature provided with an armature shaft and a motor yoke rotatably accommodating the armature. A gear case is fixed to the motor yoke, and a power supply unit that supplies a driving current to the armature is equipped to the gear case in the axial direction of the armature shaft. A sensor unit that detects rotation of the armature shaft is attached to the power supply unit in the axial direction of the armature shaft. A connector unit for connecting the power supply unit and the sensor unit to the control device is integrally formed with the power supply unit. The power supply unit is attached with the sensor unit in advance and then equipped to the gear case.