New wet chemical method so called precipitation-evaporation method was suggested for preparing spinel structure lithium manganese oxide ( LiMn 2 O 4 ) for Li ion secondary battery. Using precipitation-evaporation method, LiMn 2 O 4 cathode materials suitable for Li ion secondary batteries can be synthesized. Single spinel phase LiMn 2 O 4 powder was synthesized at lower temperature compared to that of prepared by solid-state method. LiMn 2 O 4 powder prepared by precipitation-evaporation method showed uniform, small size and well defined crystallinity particles. Li ion secondary battery using LiMn 2 O 4 as cathode materials prepared by precipitation-evaporation method and calcined at 800 ? C showed discharge capacity of 106.03mAh/g and discharge capacity of 95.60mAh/g at 10th cycle. Although Li ion secondary battery showed somewhat smaller initial capacity but good cyclic ability. It is suggested that electro-chemical properties can be improved by controlling particle characteristics by particle morphology modification during calcination and optimizing Li ion secondary battery assembly conditions.