A hydrophilization treatment agent comprising: an aqueous resin dispersion; crosslinkable fine particles; and a polyetheramine, wherein the aqueous resin dispersion comprises an ethylene-vinyl alcohol copolymer and a radical polymer having a structural unit derived from a radically polymerizable carboxylic acid monomer (A2-1), as a resin solid content; a mass ratio of the ethylene-vinyl alcohol copolymer to a mass of the radical polymer, ( /), is 0.43 to 2.33; the crosslinkable fine particles are resin particles consisting of a copolymer obtained by copolymerizing monomer components consisting of a monomer represented by the following formula, a monomer having a polyoxyalkylene chain and a polymerizable double bond, and an additional polymerizable monomer: wherein R 1 is hydrogen or a methyl group and R 2 is CH 2 or C 2 H 4; a mass ratio of the crosslinkable fine particles to a total mass of the resin solid content of the aqueous resin dispersion, ( /), is 0.11 to 1.43; the polyetheramine is a compound having a polyether chain in the main chain and an amino group on the terminal, and is polyether monoamine represented by the following formula (IV-1) or polyether diamine represented by the following formula (IV-2): wherein R 3 is a methyl or ethyl group, -(R 4 -O)- is a repeat unit derived from ethylene oxide, R 4 being C 2 H 4, a repeat unit derived from propylene oxide, R 4 being C 3 H 6, or a unit in which these coexist, and m is 1 to 100, wherein R 6 is CH 2, C 2 H 4, or C 3 H 6, R 8 is CH 2, C 2 H 4, C 3 H 6, or C 4 H 8, - (R 7 -O)- is a repeat unit derived from ethylene oxide, R 7 being C 2 H 4, a repeat unit derived from propylene oxide, R 7 being C 3 H 6, or a repeat unit in which these coexist, and n is 1 to 100;_and a mass ratio of the polyetheramine to a total mass of the resin solid content of the aqueous resin dispersion and the crosslinkable fine particles, ( /( +)), is 0.1 to 0.38. an aqueous resin dispersion; crosslinkable fine particles; and a polyetheramine, wherein the aqueous resin dispersion comprises an ethylene-vinyl alcohol copolymer and a radical polymer having a structural unit derived from a radically polymerizable carboxylic acid monomer (A2-1), as a resin solid content; a mass ratio of the ethylene-vinyl alcohol copolymer to a mass of the radical polymer, ( /), is 0.43 to 2.33; the crosslinkable fine particles are resin particles consisting of a copolymer obtained by copolymerizing monomer components consisting of a monomer represented by the following formula, a monomer having a polyoxyalkylene chain and a polymerizable double bond, and an additional polymerizable monomer: wherein R 1 is hydrogen or a methyl group and R 2 is CH 2 or C 2 H 4; a mass ratio of the crosslinkable fine particles to a total mass of the resin solid content of the aqueous resin dispersion, ( /), is 0.11 to 1.43; the polyetheramine is a compound having a polyether chain in the main chain and an amino group on the terminal, and is polyether monoamine represented by the following formula (IV-1) or polyether diamine represented by the following formula (IV-2): wherein R 3 is a methyl or ethyl group, -(R 4 -O)- is a repeat unit derived from ethylene oxide, R 4 being C 2 H 4, a repeat unit derived from propylene oxide, R 4 being C 3 H 6, or a unit in which these coexist, and m is 1 to 100, wherein R 6 is CH 2, C 2 H 4, or C 3 H 6, R 8 is CH 2, C 2 H 4, C 3 H 6, or C 4 H 8, - (R 7 -O)- is a repeat unit derived from ethylene oxide, R 7 being C 2 H 4, a repeat unit derived from propylene oxide, R 7 being C 3 H 6, or a repeat unit in which these coexist, and n is 1 to 100;_and a mass ratio of the polyetheramine to a total mass of the resin solid content of the aqueous resin dispersion and the crosslinkable fine particles, ( /( +)), is 0.1 to 0.38.