To provide a structure for installing the apron of a bathtub in which the apron can be stably installed without rattles in the apron after the apron is installed to a bathtub main body.

An installing part 4a in a fastening device 4 with the installing part 4a and an elastic fastening piece 4b is disposed to the upper bent edge 2a of an apron 2. The fastening piece 4b of the fastening device 4 disposed on the apron 2 is brought into elastic contact with the side surface of a rib 1c drooped downward at the back surface of the upper edge surface 1a of a bathtub min body 1, and the upper part of the apron 2 is inserted between the outer edge drooped part 1b of the bathtub mine body 1 and the rib 1c.