An antifogging agent composition containing a copolymer, a polyfunctional blocked isocyanate compound, an anionic surfactant (C-1), a surfactant (C-2) having a quaternary ammonium salt structure, and a fluorine-based nonionic surfactant (C-3), wherein the copolymer is a (meth)acrylate copolymer obtained from a monomer mixture containing at least one monomer (A-1) selected from the group consisting of a monomer represented by a following general formula and a monomer represented by a following general formula, a monomer (A-2) represented by a following general formula, and at least one monomer (A-3) selected from the group consisting of a monomer represented by a following general formula and a monomer represented by a following general formula: wherein R 1 is a hydrogen atom or a methyl group, R 2 is a linear or branched alkyl group having 1 to 4 carbon atoms, -C (CH 3),CH,COCH 3, -C 2 H 4 N(CH 3) 2, or -C 3 H 6 N(CH 3) 2, and R 3 is a hydrogen atom or a linear or branched alkyl group having 1 to 4 carbon atoms; wherein R 4 is a hydrogen atom or a methyl group; wherein R 5 is a hydrogen atom or a methyl group and R 6 is a linear, branched, or cyclic hydrocarbon group having 1 to 16 carbon atoms; wherein R 7 is a hydrogen atom or a methyl group and R 8 is a linear or branched alkylene group having 2 to 4 carbon atoms or -C 2 H 4 (OCO(CH 2) 5) n - wherein n is 1 to 5; and wherein R 9 is a hydrogen atom or a methyl group and R 10 is a linear or branched alkylene group having 1 to 4 carbon atoms, and wherein, per 100 parts by mass of the copolymer, an amount of the anionic surfactant (C-1) is 1 part by mass or more and 10 parts by mass or less, an amount of the surfactant (C-2) having a quaternary ammonium salt structure is 0.01 parts by mass or more and 3 parts by mass or less, and an amount of the fluorine-based nonionic surfactant (C-3) is 0.05 parts by mass or more and 5 parts by mass or less, and a mass ratio of the fluorine-based nonionic surfactant (C-3) to a total mass of the anionic surfactant (C-1) and the surfactant (C-2) having a quaternary ammonium salt structure {(C-3)/[(C-1)+(C-2)]} is 0.005 or more and 2.5 or less. the copolymer is a (meth)acrylate copolymer obtained from a monomer mixture containing at least one monomer (A-1) selected from the group consisting of a monomer represented by a following general formula and a monomer represented by a following general formula, a monomer (A-2) represented by a following general formula, and at least one monomer (A-3) selected from the group consisting of a monomer represented by a following general formula and a monomer represented by a following general formula: wherein R 1 is a hydrogen atom or a methyl group, R 2 is a linear or branched alkyl group having 1 to 4 carbon atoms, -C (CH 3),CH,COCH 3, -C 2 H 4 N(CH 3) 2, or -C 3 H 6 N(CH 3) 2, and R 3 is a hydrogen atom or a linear or branched alkyl group having 1 to 4 carbon atoms; wherein R 4 is a hydrogen atom or a methyl group; wherein R 5 is a hydrogen atom or a methyl group and R 6 is a linear, branched, or cyclic hydrocarbon group having 1 to 16 carbon atoms; wherein R 7 is a hydrogen atom or a methyl group and R 8 is a linear or branched alkylene group having 2 to 4 carbon atoms or -C 2 H 4 (OCO(CH 2) 5) n - wherein n is 1 to 5; and wherein R 9 is a hydrogen atom or a methyl group and R 10 is a linear or branched alkylene group having 1 to 4 carbon atoms, and wherein, per 100 parts by mass of the copolymer, an amount of the anionic surfactant (C-1) is 1 part by mass or more and 10 parts by mass or less, an amount of the surfactant (C-2) having a quaternary ammonium salt structure is 0.01 parts by mass or more and 3 parts by mass or less, and an amount of the fluorine-based nonionic surfactant (C-3) is 0.05 parts by mass or more and 5 parts by mass or less, and a mass ratio of the fluorine-based nonionic surfactant (C-3) to a total mass of the anionic surfactant (C-1) and the surfactant (C-2) having a quaternary ammonium salt structure {(C-3)/[(C-1)+(C-2)]} is 0.005 or more and 2.5 or less.