To provide a curable composition whereby it is possible to obtain a cured product having a high Abbe number and being excellent in transparency, crack resistance and releasability; and such a cured product. A curable composition comprises, in specific ratios, surface-modified metal oxide particles (A) having (meth)acryloyl-group-containing surface-modifying groups on the surface of the metal oxide particles, a compound (B) having a fluorine atom and at least one (meth)acryloyl group, a compound (C) having a urethane bond or —OCH2CH(OH)CH2—, having at least two (meth)acryloyl groups and having a mass-average molecular weight of at least 1,000, a compound (D) having no unsaturated bond-containing ring structure and having at least one (meth)acryloyl group, and a polymerization initiator (E).