A curable composition including: (a) 100 parts by mass of a siloxane oligomer containing at least one radically polymerizable double bond, (b) 0.001 to 1 part by mass of a fluorine-containing highly branched polymer, (c) 0.01 to 40 parts by mass of a surface modifier containing a perfluoropolyether compound, and (d) 0.1 to 25 parts by mass of a polymerization initiator generating a radical upon active energy ray irradiation, wherein the fluorine-containing highly branched polymer (b) is a fluorine-containing highly branched polymer obtained by polymerization of a monomer A containing two or more radically polymerizable double bonds per molecule and a monomer B containing a fluoroalkyl group and at least one radically polymerizable double bond per molecule in the presence of a polymerization initiator C in an amount of 5 to 200 mol % with respect to the number of moles of the monomer A.