PURPOSE: To always enable accurate initialization of a density detector by allowing the supplying of water to a detection chamber having a turbidity detector set thereon in the supply of water early in a washing process of a washing machine which is provided with the turbidity detector to detect the turbidity of washing water in a washing tank.

CONSTITUTION: A dewatering/washing machine is provided with a washing tank 4 serving as a spindrying tank concurrently in a water tank 2 and a stirring body 5 is provided on the bottom in the washing tank 4. The stirring body 5 and the washing tank 4 are rotated selectively with a drive mechanism 7 mainly composed of a motor 6. In this case, a detection chamber which is sunk downward into the bottom part of the washing tank 3 from thereinside is formed in a connection case 10 mounted at a drain port 8 and an air trap and a turbidity detector comprising a photoelectric element is provided in the detection chamber. A water supply port connected to a cold water supply hose 17 is formed at a place facing the turbidity detector in the connection case. In the supply of cold water early in the washing process, the stirring body 5 is rotated for a specified time and the turbidity detector is initialized based on subsequent output values of the turbidity detector.