A takedown pet nail grinder includes a rectangular, inclined platform including four downward extending tabs at four corners respectively, and front, rear, and two side stops wherein each of the front and rear stops have an inward bending part two triangular side panels each including first projections formed on a first edge, second projections formed on a second edge, and third projections formed on a third edge a rectangular rear panel including protrusions formed on both sides respectively and a hard board disposed on a top surface of the platform. The tabs are inserted into the side panels for being positioned. The first, second, and third projections are inserted into the platform for being positioned. The protrusions are inserted into the side panels for being positioned. Front and rear ends of the hard board are restrained by the bending parts respectively.