A temperature-responsive hydrogel which contains a carboxyl group-bearing polymer and a divalent-metal salt of an organic acid is provided. The carboxyl group-bearing polymer may be a homopolymer of a carboxyl group-bearing monomer or a copolymer of a plurality of monomers including the monomer. A method for producing the temperature-responsive hydrogel involves immersing a carboxyl group-bearing polymer in an aqueous solution of a divalent-metal salt of an organic acid. The concentration of the divalent-metal salt of an organic acid in the aqueous solution may be 50 mM to the saturation concentration. It is possible to provide a temperature-responsive gel having an LCST with no volume phase transition and a method for producing the temperature-responsive gel.