A novel antifouling paint composition is disclosed. The antifouling paint composition comprises a resin of 5 to 20 wt %, a solvent of 3 to 30 wt %; a polyhexamethyleneguanidine salt of the following chemical formula 1 of 0.05 to 20 wt %, a pigment of 1 to 50 wt %; and cuprous oxide of 22 to 75 wt % and/or zinc pyrithione of the following chemical formula 2 of 0.05 to 20 wt %; ##STR00001## ##STR00002## wherein in chemical formula 1, X can be the same or different, and at least one of X is an inorganic acid salt or an organic acid salt; R.sub.1 can be the same or different, and is a linear or branched alkyl group containing from 1 to 20 carbon atoms, a phenyl group, a chlorophenyl group, a bromophenyl group, an iodophenyl group, a benzyl group, a chlorobenzyl group, a bromobenzyl group, a iodobenzyl group, a phenethyl group, a naphthyl group or a hydrogen; and n is an integer of 1 or more.