The present invention addresses the problem of providing a photopolymerization initiator composition which exhibits excellent storage stability at low temperatures and is excellent in terms of suppressing bleed out at the surface of a cured product following a thermocycle test; an active energy ray-curable composition; and a cured product. This photopolymerization initiator composition contains a photopolymerization initiator represented by general formula (I) and at least one type of additive selected from the group consisting of compounds represented by general formulae (II) to (IV).
