To eliminate such an inconvenience as to bend forward when the toilet seat is leaped up, and also cleanly enable the leaping up of the seat.

A link 3 is fixed to the end part of the extension of the turning shaft 2 of a toilet seat 1 at right angles, and a pedal 4 is installed on the installation surface B of a toilet body 10, and the pedal 4 and the fixing part of the link 3 situated on the opposite side are turnably connected by means of a connecting rod 5. When the pedal 4 is trodden on so as to turn the seat, the connecting rod 5 turnably connected to the pedal 4 is pulled to draw the link 3 that has been connected to the other end of the connecting rod 5, so that the turning shaft 2 of the toilet seat 1 to which the link 3 has been fixed at right angles is turned to leap up the seat 1. The dimensions of the link 3 and the connecting rod 5 and the fitting angle thereof or the like are determined so that the toilet seat 1 is stopped at an angle just before the plate surface thereof becomes vertical in the state that the pedal 4 has been trodden on to the maximum. Then, when the treading-on of the pedal 4 is released, the toilet seat 1 falls toward the user by its own weight, and returns to its initial state together with the pedal 4.