Antifouling coating composition

An antifouling coating composition, comprising:

• a hydrolyzable copolymer (A) containing an organosiloxane block and a metal ester group, and zinc oxide (B);
• wherein the copolymer (A) comprises:
• 5 to 25% by mass of a constituent unit derived from a metal ester group-containing monomer (a1);
• 5 to 15% by mass of a constituent unit derived from an organosiloxane block-containing monomer (a2) represented by formula (2);
• and
• a constituent unit derived from a monomer (a3) represented by formula (3);
• and
• a content of the zinc oxide (B) relative to 100 parts by mass of the content of the copolymer (A) is 70 to 200 parts by mass:
• wherein R1, R2, and R3 each independently represent a monovalent hydrocarbon group;
• X each independently represent a (meth)acryloyloxyalkyl group or a mercaptoalkyl group;
• m is 1 or greater;
• n is 0 or greater;
• p and q are each independently 0 or 1;
• and
• n+p+q is 1 or greater;
• wherein R41 represents a monovalent group including an ethylenically unsaturated group;
• and
• R42 represents a monovalent hydrocarbon group with 3 to 6 carbon atoms being free of an ethylenically unsaturated group.