The present invention provides a thermosetting and photocurable coating composition comprising: (A) at least one compound selected from the group consisting of radical-polymerizable unsaturated monomers, resins containing radical-polymerizable unsaturated groups, and resins containing radical-polymerizable unsaturated groups and thermosetting functional groups; (B) a hydroxyl-containing polyester resin produced by esterifying a polybasic acid (a) and a polyhydric alcohol (b), wherein an alicyclic polybasic acid (a1) and/or an alicyclic polyhydric alcohol (b1) are included in a ratio of 20% or more based on the total weight of polybasic acid (a) and polyhydric alcohol (b); (C) a crosslinking agent; and (D) a photopolymerization initiator; and a method of forming a coating film using the coating composition.