To provide a cleaning method for a die, in which management of the same is made easy by instantly removing a remaining substance sticking the surface of the die for molding a synthetic resin and rubber or the like.

A projection material is obtained by pulverizing a composite resin molded body consisting of both one kind or two or more kinds selected from melamine, phenol, unsaturated polyester, epoxy, ketone and a guanamine resin or a copolymer of these resins and a urea resin and nearly homogenizing the composite resin molded body in a range within 200-3000 μm grain size. The remaining substance sticking the surface of the die is removed by blowing the projection material together with air flow on the surface of the die.