A clean toilet seat capable of covering the toilet seat with a toilet seat cover sheet automatically, securely and quickly, with such a cover sheet being replaced at each time of use so that people can always avoid contact with skin of others, is provided. In a thing having a toilet seat body placed on a surface of a toilet stool body, and an opening and closing lid pivotally mounted to the toilet seat body and covering a surface of the toilet seat, a plurality of cover sheets are housed in the above-described opening and closing lid, and on an occasion of movement to close the opening and closing lid, the cover sheet covers the surface of the toilet seat body.