To provide an alkaline battery, having superior high-temperature storage characteristic and little characteristic deterioration in high temperature storage.

An alkaline battery is formed by using a negative electrode with a hydrogen absorbing alloy as a negative active material and a positive electrode with a metal oxide as a positive active material and with added complex oxide represented by a formula ACoxM1-xO2 (where, A represents alkali metal element, x is such that 0≤x<1, M is at least two elements including Co or at least one element which includes Ni. It is especially preferable to include Co and Ni as a complex oxide represented by formula ACoxM1-xO2.