There is disclosed an alkaline battery including a positive electrode material mixture, a negative electrode, a separator interposed between the positive electrode material mixture and the negative electrode, and an alkaline electrolyte, wherein the positive electrode material mixture includes a first active material comprising nickel oxyhydroxide and a second active material comprising manganese dioxide, the nickel oxyhydroxide includes a .gamma.-type crystal structure, the content of nickel in the nickel oxyhydroxide is not less than 45 wt %, and the average particle diameter on a volume basis of the nickel oxyhydroxide measured with a laser diffraction particle size distribution analyzer is 3 to 20 .mu.m.