The present invention provides an adhesive, high water content gel that does not cause a heat generation problem even when used as a patient plate for electrosurgical units through which high current flows and that is excellent in adhesion, as well as an electrode pad including the gel. The present invention relates to an adhesive, high water content hydrogel 14 containing a polymer matrix that includes a copolymer of a polymerizable monomer and a crosslinkable monomer, water, a polyhydric alcohol, an electrolyte, polyacrylic acid, and polyvinyl alcohol, the hydrogel containing, based on 100% by weight of the total hydrogel, 40-70% by weight of water, 1.0-5.0% by weight of polyacrylic acid, and 0.5-5.0% by weight of polyvinyl alcohol, and being produced by copolymerization. An electrode pad 11 is also obtained by coating a conductive layer 13 formed on a base film 12 with the adhesive, high water content hydrogel 14.
