An active energy ray-curable resin composition comprising at least a multifunctional monomer having three or more radical polymerizable functional groups in the molecule: wherein a composition of the resin composition comprises: a multifunctional monomer and a mono(meth)acrylate having a polyethylene glycol structure having a number of repeating ethylene glycol units of 9 or more, wherein the content of multifunctional monomer is 70 to 95 parts by mass, and the content of mono(meth)acrylate is 5 to 30 parts by mass (wherein the total of contents of all the monomers contained in the resin composition is 100 parts by mass), wherein the multifunctional monomer has three or more radical polymerizable functional groups in the molecule, and a value obtained by dividing molecular weight of the multifunctional monomer by the number of radical polymerizable functional groups (molecular weight per functional group) is 110 to 200; or a polymerizable component comprising 15 to 70% by mass of a multifunctional monomer which has three or more radical polymerizable functional groups in the molecule, molecular weight per functional group of less than 110, and no ethyl group in the terminal; 15 to 50% by mass of a multifunctional monomer which has three or more radical polymerizable functional groups in the molecule, molecular weight per functional group of 110 or more, and no ethyl group in the terminal; and 15 to 40% by mass of a bifunctional monomer which has two radical polymerizable functional groups and four or more oxyethylene groups in the molecule, and no methyl group in the terminal, and further comprising a photoinitiator. wherein a composition of the resin composition comprises: a multifunctional monomer and a mono(meth)acrylate having a polyethylene glycol structure having a number of repeating ethylene glycol units of 9 or more, wherein the content of multifunctional monomer is 70 to 95 parts by mass, and the content of mono(meth)acrylate is 5 to 30 parts by mass (wherein the total of contents of all the monomers contained in the resin composition is 100 parts by mass), a multifunctional monomer and a mono(meth)acrylate having a polyethylene glycol structure having a number of repeating ethylene glycol units of 9 or more, wherein the content of multifunctional monomer is 70 to 95 parts by mass, and the content of mono(meth)acrylate is 5 to 30 parts by mass (wherein the total of contents of all the monomers contained in the resin composition is 100 parts by mass), wherein the multifunctional monomer has three or more radical polymerizable functional groups in the molecule, and a value obtained by dividing molecular weight of the multifunctional monomer by the number of radical polymerizable functional groups (molecular weight per functional group) is 110 to 200; or a polymerizable component comprising 15 to 70% by mass of a multifunctional monomer which has three or more radical polymerizable functional groups in the molecule, molecular weight per functional group of less than 110, and no ethyl group in the terminal; 15 to 50% by mass of a multifunctional monomer which has three or more radical polymerizable functional groups in the molecule, molecular weight per functional group of 110 or more, and no ethyl group in the terminal; and 15 to 40% by mass of a bifunctional monomer which has two radical polymerizable functional groups and four or more oxyethylene groups in the molecule, and no methyl group in the terminal, and further comprising a photoinitiator. a polymerizable component comprising 15 to 70% by mass of a multifunctional monomer which has three or more radical polymerizable functional groups in the molecule, molecular weight per functional group of less than 110, and no ethyl group in the terminal; 15 to 50% by mass of a multifunctional monomer which has three or more radical polymerizable functional groups in the molecule, molecular weight per functional group of 110 or more, and no ethyl group in the terminal; and 15 to 40% by mass of a bifunctional monomer which has two radical polymerizable functional groups and four or more oxyethylene groups in the molecule, and no methyl group in the terminal, and further comprising a photoinitiator.