According to an aspect of the invention, a toilet apparatus includes a toilet, a bowl configured to receive solid waste being formed in the toilet, the bowl being hydrophilic; a spray unit configured to spray at least one selected from water and hypochlorous acid water onto a surface of the bowl; a detection unit configured to detect a state of use of the toilet; and a control unit configured to spray at least one selected from the water and the hypochlorous acid water from the spray unit before the use and to spray the hypochlorous acid water from the spray unit after the use. The cleanliness of the bowl surface of a toilet can be maintained by suppressing the affixation of solid waste and the propagation of bacteria caused by oil.