PURPOSE: To easily equalize a temperature in a sauna room by providing the air ventilation device having many holes in a suitable position on the upper side of a heat source provided in the lower part of a floor part, and dispersing high temperature air generated by the heat source and emitting it to the upper part.

CONSTITUTION: In the private low temperature sauna room structure body which can set a room temperature to a temperature range of 40°C-90°C, plural heat sources 2 are provided in the lower position of a floor part (far infrared radiation radiator) 1 consisting of a far infrared radiation member. Heat generated from this heat source 2 is subjected to electromagnetic radiation into a sauna room through the far infrared radiation radiator 1. Also, in this case, an air ventilation device 6 consisting of a plate-like member 7 having many through holes 8 is provided in a suitable position on the upper side of these heat sources 2, so that high temperature air generated by the heat source is dispersed and emitted to the upper part. In such a way, a temperature in the sauna room is equalized easily.