The present invention provides a redox-curing type composition that penetrates into a wet body, particularly into a tooth structure (dentin), is cured in an accelerated manner by the moisture contained in the wet body, thereby exhibits a higher bond strength than those of conventional redox-curing type compositions, and has satisfactory storage stability. The present invention is a redox-curing type composition including a polymerizable monomer (a) having an acidic group, a polymerizable monomer (b) having no acidic group, a powdery inorganic peroxide (c) with an average particle diameter of 0.01 to 50 μm, an amine-based reducing agent (d), and a polymerization accelerator (e). The amine-based reducing agent (d) includes an aromatic amine (d−1) and an aliphatic amine (d−2), and a weight ratio (d−1):(d−2) therebetween is 5:1 to 1:50.