PROBLEM TO BE SOLVED: To provide a polymerizable dental separating agent having less stickiness and easily removable. A radically polymerizable compound (A) and a polymerization initiator (B) are contained, a thickness of an unpolymerized layer after curing is 100 μm or less, a flexural modulus is 1.50 GPa or less, and total destruction. A polymerizable dental separating agent whose work is 5.0 kJ/m 2 or more. [Selection diagram] None【課題】ベタツキが少なく、かつ容易に除去可能な重合性歯科用分離剤の提供。【解決手段】ラジカル重合性化合物(A)、及び重合開始剤(B)を含有し、硬化後の未重合層厚みが100μm以下であり、曲げ弾性率が1.50GPa以下であり、かつ全破壊仕事が5.0kJ/m2以上である、重合性歯科用分離剤。【選択図】なし