To provide an antifouling coating composition which does not contain copper or any copper compound (e.g., cupric oxide) and therefore enables the production of an antifouling coating film that does not undergo discoloration or cracking caused by ultraviolet ray or moisture, can have a low VOC and long-term antifouling properties at high levels simultaneously, and has excellent mechanical strength. A two-part hydrolysable antifouling coating composition of the present invention comprises two liquids, i.e., a first component containing a polyester resin having a solid content acid value and a hydroxyl value of 50-200 mgKOH/g and 100 mgKOH/g or less, respectively, and having a viscosity of 500 mPa·s or less at 25°C and a second component in paste form containing a zinc oxide, and based on the total amount of the first and second components, the content of volatile organic compound is 400g/L or less, and copper or any copper compound is not contained.
