Decorating powder composition

[Problem] To provide a decorating powder composition for decorating the surface of a solid cosmetic material, in particular, for obtaining a solid cosmetic material having a beautiful appearance which is decorated with a glossy powder, and a decorating method using the decorating powder composition.[Solution] Provided are a decorating powder composition including a glossy powder which has been surface-treated with a silane compound or a silazane compound, and a method for decorating a solid cosmetic material, the method including causing the decorating powder composition to adhere to a printing plate and then bringing the printing plate into contact with a surface of the solid cosmetic material to transfer the decorating powder composition to the surface of the solid cosmetic material and decorate the solid cosmetic material.