An active ester compound that can form a cured product having excellent dielectric properties and copper foil adhesion properties is provided, a curable composition including the active ester compound is provided, and a cured product of the curable composition is provided. Also provided are a semiconductor encapsulating material, a printed wiring board, and a build-up film formed by using the curable composition. Specifically, an active ester compound is provided which includes a fluorinated hydrocarbon structural moiety and a plurality of aromatic ester structural moieties in the structure of the molecule and includes an aryloxycarbonyl structure or an arylcarbonyloxy structure at an end of the molecule, a curable composition including the active ester compound, and a cured product of the curable composition, and also provided are a semiconductor encapsulation material, a printed wiring board, and a build-up film formed by using the curable composition.