To provide an antifouling resin compsn. which does not have such a toxicity as that of a tin compd. and is excellent in antifouling properties and to provide a process for producing the same.

This compsn. is produced by reacting an antifouling resin compsn. contg., as the acting component, at least one resin which has a metal carboxylate group in the molecule and is selected from among resins represented by formulas I, II, and III (wherein Rp is a base resin; M is a divalent metal atom; m is an integer of 1-10; n is an integer of 0-10; and k is an integer of 0-10) with a carboxylated resin and a divalent metal oxide or hydroxide in the presence of 6-30wt.% water.