A secondary battery includes: a cathode; an anode; and a gel electrolyte. The gel electrolyte includes an electrolytic solution and a polymer compound. The electrolytic solution includes an unsaturated cyclic ester carbonate represented by the following Formula (1), where X is a divalent group in which m number of >C═CR1-R1 and n number of >CR3R4 are bonded in any order; each of R1 to R4 is one of a hydrogen group, a halogen group, a monovalent hydrocarbon group, a monovalent halogenated hydrocarbon group, a monovalent oxygen-containing hydrocarbon group, and a monovalent halogenated oxygen-containing hydrocarbon group; any two or more of the R1 to the R4 are allowed to be bonded to one another; and m and n satisfy m≧1 and n≧0.