According to one embodiment, a secondary battery includes a positive electrode, a negative electrode, a separator layer, and a nonaqueous electrolytic solution. The separator layer includes a first porous layer containing a solid electrolyte and a second porous layer containing fibers. The second porous layer is in contact with a first surface of the first porous layer. The nonaqueous electrolytic solution includes a first solvent including at least one of methyl propionate and ethyl propionate, and a second solvent different from the first solvent. The first porous layer has a void fraction of 10% by volume or greater and 50% by volume or less. The second porous layer has a void fraction greater than the void fraction of the first porous layer.