To facilitate the setting of the optimum bathing environment for a person taking a bath by himself/herself.

A name of a bathing person and an individual basic data are registered into a processing unit 33 by a data input device 31. The unit 33 finds the optimal value of bathing environment improvement based on the basic data, physical condition data, seasonal data, and a bathing environment improvement program and the operation of devices 1-5 and a hot water supply device 11 is started. A bathing guide 29 informs the completion of the bathing preparation and a shower temperature is started to be controlled. When a seating sensor 13 judges the bathing of the bathing person, the number of bathing ad the bathing time per a bathing are started to be counted. The bathing residual time is displayed on a bathing time display 7 and after passing a prescribed time from the start of the bathing, additional heating of the hot water supply device 11 is started so as to raise the bathtub water temperature based on the set value of the bathtub water increase temperature in continuous bathing. A bathing notice device 9 informs or alarms the residual time from one minute before completing the bathing control time. When the bathing person takes a bath again, the bathing control time is reset.