To obtain a composition for coating materials excellent in weather and fouling resistances and further ply adhesion to a primer or ply adhesion at the time of recoating.

This composition for coating materials comprises (A) a polymer containing hydroxyl groups or alkoxysilyl groups, (B) a hydrolytic condensate of an alkoxysilane, (C) a compound having urethane bond and a hydrolyzable silyl group in one molecule and (D) an organic solvent. The polymer containing the hydroxyl groups or alkoxysilyl groups is preferably an acrylic or a methacrylic polymer or a fluorine-containing polymer soluble in organic solvents.