An alkaline battery of the present invention includes a positive electrode material mixture including nickel oxyhydroxide. The nickel oxyhydroxide includes a secondary particle with a crystal structure mainly composed of .gamma.-type at least a portion of the surface layer of the secondary particle, and with a crystal structure mainly composed of .beta.-type in the inner portion of the secondary particle. Based on the present invention, the advantage of the alkaline battery, i.e., excellence in discharge performance under high-load, can be kept and the conventional problem of storage characteristics can be improved.