The antifouling coating composition of the present invention is a antifouling paint composition which is substantially free of organic tin and cuprous oxide, A metal-containing copolymer obtained by copolymerizing a polymerizable unsaturated monomer containing a metal (A) and (a1), a radical polymerizable unsaturated monomer containing no metal and (a2), And -2-n- octyl-4-3-one (B) 4,5- dichloro And is characterized by containing the (C) metal pyrithione compound. In accordance with the present invention, has a stain resistance environmental impact excellent small, and excellent uniformity exhaustion of the coating film, moreover antifouling coating composition excellent in maintaining performance soil-resistant long-proof coating, anti so that it is possible to provide a ship, underwater structures, fishing nets or fishing gear that has been coated with a coating film dirty Kitananurimaku,-proof.本発明の防汚塗料組成物は、亜酸化銅および有機スズを実質的に含まない防汚塗料組成物であって、(A)金属を含有する重合性不飽和単量体(a1)と、金属を含有しないラジカル重合性不飽和単量体(a2)とを共重合してなる金属含有共重合体と、(B)4,5-ジクロロ-2-n-オクチル-4-イソチアゾリン-3-オンと、(C)金属ピリチオン化合物とを含有することを特徴としている。本発明によれば、環境への負荷が少なく優れた防汚性を有し、塗膜の均一消耗性に優れ、しかも塗膜の長期防汚性維持性能に優れた防汚塗料組成物、防汚塗膜、該防汚塗膜で被覆された船舶、水中構造物、漁具または漁網を提供することができる。
