A method for producing a cathode material for a lithium battery, characterized in that it comprises admixing a compound liberating a phosphate ion in a solution and metallic iron, and dissolving the metallic iron, followed by firing, thereby synthesizing ferric phosphate. The above method further comprising reacting a raw material mixture while grinding it down or refluxing can produce ferric phosphate cathode material having a fine particle diameter and exhibiting high activity, through a precursor before firing having a fine particle diameter.