Provided is a motor control device having a function for determining a rotor position of a synchronous motor, without use of a sensor, the device prevents obtaining an erroneous rotor position, to enable stable control of the synchronous motor based on the rotor position in both the normal-control region and the flux-weakening-control region. The motor control device 1 includes: a first rotor position determining unit 19 that determines a rotor position of the synchronous motor 2 based on a current electrical angle, and a first current phase obtained from a current peak value and a difference between an induced voltage electrical angle and a current electrical angle; a second rotor position determining unit 20 that determines the rotor position of the synchronous motor 2 based on the current electrical angle, and a second current phase obtained from a flux linkage and the current peak value; and a selecting unit 21 that selects the first rotor position determining unit 19 or the second rotor position determining unit 20, based on the current peak value, and the first current phase or the second current phase.