PROBLEM TO BE SOLVED: To provide a photocurable composition capable of achieving a high photocuring depth by reducing the amount of unpolymerized surface of a cured product obtained, and in particular, a photocuring type lining material for a denture base. It is an object of the present invention to provide a photocurable composition that can be suitably used for a photocurable composition. SOLUTION: Polymerizable monomers such as 2-methacryloxyethyl purpionate and 1,9-nonamethylene methacrylate, resin particles such as spherical polyethyl methacrylate particles, α-diketone compounds such as camphorquinone, p-dimethyl Includes tertiary amine compounds such as ethyl aminobenzoate and α-hydroxycarboxylic acids having an acid dissociation constant of 3.0 or more in water (25 ° C.) such as malic acid and having two or more carbonyl groups in the same molecule. Photocurable composition. [Selection diagram] None【課題】 得られる硬化体の表面未重合量を低減し、高い光硬化深さを達成することができる光硬化性組成物を提供することにあり、特に光硬化型の義歯床用裏装材に好適に用いることができる光硬化性組成物を提供することにある。【解決手段】 ２－メタクリロキシエチルプルピオネート及び１，９－ノナメチレンメタクリレート等の重合性単量体、球状ポリエチルメタクリレート粒子等の樹脂粒子、カンファーキノン等のα－ジケトン化合物、ｐ－ジメチルアミノ安息香酸エチル等の第三級アミン化合物及びリンゴ酸等の水中（２５℃）での酸解離定数が３．０以上で同一分子内にカルボニル基を２つ以上有するα－ヒドロキシカルボン酸を含む光硬化性組成物。【選択図】 なし
