PURPOSE: To provide a lavatory and a chair device for medical treatment which can be pulled out to be used in a certain position of a bed automatically and stored in a box body automatically after usage.

CONSTITUTION: This lavatory and a chair device for medical treatment is provided with a stand part 3 placed freely side-movingly by means of a cylinder 2 in a side position of a bed 1, a box body 4 placed freely longitudinal-movingly by means of the cylinder 2 on the stand part 3, and two lid parts 5 placed freely falling-type opening/closing by means of two cylinders on the same height as that of the bed 1 at the bed 1 side of the box body 4, a chamber pot 7 which is always kept vertical by be supported freely swingingly by means of a supporting part 6 formed at a right angle inside of the one lid part 5, and a chair 8 provided at a right angle inside of the other lid part 5.