An object of the present invention is to provide an antifouling paint composition which shows an excellent antifouling effect in seawater for a long period of time, and has excellent adhesion and recoating properties to a substrate. The present invention relates to an antifouling pain composition comprising a copolymer which is obtained by polymerizing a monomer mixture comprising silicon-containing polymerizable monomer (a) having two (meth)acryl end groups, and which contains bivalent metal atom. The copolymer is also obtained by polymerizing a monomer mixture comprising silicon-containing polymerizable monomer (b) having one (meth)acryl end group, and metal atom containing polymerizable monomer (c,) having two unsaturated groups and metal atom selected from Mg, Zn, and Cu.