Olivine-structured LiMnPO4 with uniform cluster-like and rod-like morphologies have been synthesized via a simple solvothermal process in water–organic solvent mixtures. The cluster-like LiMnPO4 microstructures are composed of numerous nanoplates in thickness of ca. 35nm and width of ca. 400nm. Carbon is coated on the LiMnPO4 surfaces by chemical vapor deposition (CVD) from methylbenzene and ball milling with acetylene black, respectively. The hierarchical LiMnPO4 nanoplates deliver much higher discharge capacity and rate capability than the nanorods due to the larger interfacial area for electrochemical reaction and shorter lithium ion diffusion depth. Furthermore, carbon-coating via CVD approach leads to a significant improvement in the electrochemical performances compared to the ball milling process.