To provide a human body private parts washing device comfortable to a user and hard to get any trouble therewith.

A human body private parts washing device is constituted of a washing nozzle 103 for washing the private parts, a washing controller 2 for executing the movement of the front end of the washing nozzle, the injection stop of washing water, the adjustment of the volume of washing water, etc., and a control switch 23 for operating the washing controller 2. Then, a flow adjusting valve 5 is constituted of a cylindrical valve shaft connecting the shaft to the shaft of a motor by receiving supply of washing water from one end to close the other end, the valve shaft having an opening for sending washing water supplied to the curved surface thereof to the washing nozzle, a valve body storing the valve shaft therein by the motor in a rotatable manner and the valve body having a water outlet provided so as to overlap at least the opening mounted to the valve shaft, and while a controlling circuit is operated, after the valve shaft is rotated in the valve body every certain time, it is in a waiting state.