Plate-like LiMnPO4 particles were prepared by polyol method. The chemical and physical properties of plate-like LiMnPO4 particles were characterized by XRD and SEM. The thickness of plate-like LiMnPO4 particles was approximately 35 nm. XRD pattern of plate-like LiMnPO4 was good agreement with orthorhombic olivine structure. The first discharge capacity of C/LiMnPO4 cathode was approximately 95 mAh/g. 99.9 % of initial discharge capacity was maintained after 100 cycles.