A washing machine includes a rotational tub, a single-phase induction motor driving the rotational tub in a dehydrating operation and having a main and an auxiliary coils, a speed detector for detecting a speed of the motor, thereby generating a detection signal, and an output changeover device for changing between an operation mode in which both of the main and auxiliary coils are excited and the other operation mode in which either the main or auxiliary coil is excited. When the motor speed is increased in the dehydrating operation, a control circuit controls the motor in a feedback manner. More specifically, in low and medium speed ranges, the control circuit executes a control pattern in which both of the main and auxiliary coils are excited and selectively executes another control pattern in which only the auxiliary coil is excited when necessary.