There is provided an adhesive agent exhibiting high adhesive strength to polyolefin. An adhesive agent contains a chloroprene copolymer latex containing a chloroprene copolymer (A) and a metal oxide (B). The chloroprene copolymer (A) is a copolymer of a monomer group containing chloroprene (A-1), α,β-unsaturated carboxylic acid (A-2), and 2, 3-dichloro-1,3-butadiene (A-3). The chloroprene copolymer (A) has a tetrahydrofuran-soluble component soluble in tetrahydrofuran and the weight average molecular weight of the tetrahydrofuran-soluble component is 80000 or more and 140000 or less. When the amount of the metal oxide (B) based on 100 parts by mass of the chloroprene copolymer (A) is defined as Y part(s) by mass and the weight average molecular weight of the tetrahydrofuran-soluble component is defined as X, the content of the metal oxide (B) satisfies Formula: -1.2 × X/100000 + 1.6