An alkaline storage battery having excellent self-discharge characteristics even after a number of charge-discharge cycles is provided. The alkaline storage battery is provided with a case and an electrode group enclosed in the case, and a separator that is included in the electrode group retains at least 15 mg/cm2 of an electrolyte at least in a period after assembling the battery, from the time the separator is impregnated with the electrolyte to the time the battery is activated.