To provide an auxiliary seat for a Western-style toilet for taking a seated posture in a Japanese style toilet, giving a sense of security when seated, and using in training an infant to do evacuation and urination.

A seating surface 1 is provided with a through-part 2, and wall surfaces 5 disposed in the periphery thereof. A handle 3 is provided in front of the seating surface, and leg parts 4 are provided on the lower parts of the front of the seating surface.