A manufacturing method for a thin board-shaped fired piezoelectric body has: a step of manufacturing, using a piezoelectric material, a green sheet having a ratio T/L of 0.000002 to 0.2, where T is the thickness and L is the maximum length within the surface after firing; and a step of obtaining the thin board-shaped fired piezoelectric body with reinforcing members for firing by performing firing after disposing the reinforcing members for firing by scattering at least on one surface of the green sheet so as to exclude the areas to be the thin board-shaped fired piezoelectric body later. The piezoelectric body which has excellent planarity and a thin board shape can be manufactured at low cost by the method.