In a motor driving apparatus having an inverter which can drive n (n being an integer not smaller than 2) motors each having a permanent magnet in its rotor, and a connection switching device for switching the connection state of the n motors, the connection switching device is operated to change the number of the motors connected to the inverter thereby to change the impedance as seen from the inverter towards the motors. When i (i being any of 2 to n) motors among the n motors are concurrently driven by the inverter, the voltage outputted by the inverter may be controlled such that the inductance values of the i motors are identical. It is possible to prevent hunting and step-out due to the phase difference between the motors driven by the inverter.