The object of the present invention is to provide a coating composition which can provide a coating film having excellent adhesion to a chromium thin film under various conditions, and sufficient scratch resistance, and the present invention provides a coating composition for a chromium thin film formed on a substrate, wherein the coating composition includes: an acrylic copolymer (A) having a phosphate group and a hydroxyl group other than a hydroxyl group in the phosphate group; isocyanate (B); and a metal chelate (C).