An active energy beam-curable composition is provided, which is excellent in coatability to films and safety, and particularly suitable for use in a light diffusion film since a light diffusion film made of a cured product of the composition is excellent in both haze and total light transmittance. The active energy beam-curable composition comprises an ethylenically unsaturated group-containing compound (A) that contains, as an essential component thereof, a compound having an ethylenically unsaturated group and an aromatic group, and a granular substance (B) that is insoluble in the component (A), in which the subtraction of the refractive index of the component (B) from the refractive index of a cured product of the component (A) alone is not less than 0.03 and not more than 0.18.