The present invention provides a curable composition allowing a cured product having high aesthetic quality, strength and durability along with having high surface lubricating property. A curable composition in the present invention comprises: an inorganic powder and a polymerizable monomer, wherein the inorganic powder contains a spherical composite powder, the spherical composite powder has a complex of silicon dioxide and at least one of alumina and zirconia, and an amorphous part and a crystalline part are mixed in the spherical composite powder. A refractive index difference is not more than 0.05 between the spherical composite powder and a cured product obtained by curing only a compound excluded the spherical composite powder.