To provide a spout device for a bathtub, with which water film can be effectively showered over the bathing person's section good for blood circulation and a favorable massage effect can be easily obtained, while a water film formation device can be easily installed even in an existing bathtub and can expand its versatility.

A water film formation device which is formed separately from a bath and has a horizontal slit-shaped spout is installed above an upper edge face of the bathtub, and is the water film formation device which spouts water into the bathtub through the spout of the water film formation device and makes water film in a desired shape, and the height of the water film formation device is set 500-800 mm from the bathing seat surface of the bath of the spout. The water film formation device forms the water film approximate U-shaped in cross section so that the water film can hit the neck, the shoulder, the back or the like avoiding the bathing person's head.