An electric motor control device includes a control section adapted to control supply of a drive current to an electric motor, and a rotational speed detection section adapted to detect a rotational speed of the electric motor, the drive current includes a d-axis current and a q-axis current, and the control section calculates a q-axis current command value based on a torque command value to the electric motor, calculates a d-axis current command value using a difference between the rotational speed of the electric motor and a previously determined base rotational speed of the electric motor, and the q-axis current command value, and performs vector control on the electric motor using the d-axis current command value and the q-axis current command value.