A curable composition is provided and contains (A) at least either a hydrolyzed product of organosilane or a condensation reaction product of the hydrolyzed product having a mass average molecular weight of from 500 to 10,000 in terms of ethylene glycol, (B) a fluorine-containing resin having a mass average molecular weight of 5,000 or more in terms of polystyrene, and a fluoroalkyl structure and a polysiloxane structure, and (C) a silane coupling agent represented by a prescribed formula or at least either a hydrolyzed product of the silane coupling agent or a condensation reaction product of the hydrolyzed product.