To provide a curable composition exhibiting sufficiently high transparency when containing a large amount of a metal as an inorganic substance.

The curable composition includes a polymerizable monomer and a metal alkoxide represented by general formula M(OR)n (1) (wherein M is at least one selected from the group consisting of Al, Si, Ti, Y, Zr, Nb, Cd, Ba, Ta and Ce; R is a specific group having general formula (2); R¹s are each vinyl or alkyl which may be substituted with hydroxy; n is an integer of 2-5).