The invention discloses a self-cleaning closestool and a preparation method thereof. The method comprises the following steps: mixing green body raw materials according to the proportion, and then carrying out ball milling on the green body raw materials and a grinding ball according to the mass ratio being 1 to (3 to 4) to obtain petuntse; mixing the petuntse with water, and carrying out slip casting and drying to obtain a closestool green body; grinding titanium dioxide and zirconium oxide in an active additive of an enamel layer raw material to be 270 to 400 meshes, then adding a ground material into an ethanol solution, standing for 24 to 48 hours, filtering and drying; calcining a dried substance at the temperature of 1850 to 2500 DEG C for 2 to 4 hours, and then mixing the calcined substance with remaining active additive raw materials to obtain a self-cleaning glaze; spraying the self-cleaning glaze on the closestool green body, calcining the closestool green body at the temperature of 1200 to 1600 DEG C for 0.5 to 1 hour, then cooling to be 1000 to 1100 DEG C and calcining for 0.5 to 1 hour to obtain the self-cleaning closestool. The method disclosed by the invention has the advantages of high-efficiency cleaning effect, easily-obtained formula raw materials and simplicity in preparation.