To provide a drum-type washing machine including a motor driving device capable of performing boost control of a DC voltage supplied to an inverter circuit under an appropriate condition according to a difference between a target rotation number Nt and a present rotation number Np of a drum motor.

A DC voltage Vd output from a rectifier circuit 36 via smoothing capacitors 37 and 38 is applied to a first inverter circuit 25 for driving and controlling a drum motor 7. A control section 30 for driving the first inverter circuit generates a short-circuit signal making a short-circuit control element conductive at least during part of the period of a dewatering step with a zero-cross detection point of an AC power supply voltage as a starting point. A pulse width Tw of the short-circuit signal is set on the basis of a target voltage Vt of the DC voltage Vd, which is set according to a difference between a target rotation number Nt and a present rotation number Np of the drum motor, and a detection value of the DC voltage Vd.