A high-solid-content coating composition including: (A) an acrylic resin containing a hydroxyl group and an alkoxysilyl group; (B) a polyester resin containing a hydroxyl group; and (C) a polyisocyanate compound, in which the acrylic resin (A) containing a hydroxyl group and an alkoxysilyl group is contained in an amount of 20 to 50 parts by mass per 100 parts by mass of resinous solid components of the high-solid-content coating composition, the polyester resin (B) containing a hydroxyl group has an acid value of 10 mg-KOH/g or less, a hydroxyl value of 180 to 300 mg-KOH/g, and a number-average molecular weight of 400 to 1,500, and the coating composition, when being applied, has a solid content of 50 mass % or more.