Olivine-like LiMnPO 4 was prepared from the NH 4 MnPO 4 ·H 2 O precursor precipitated from the aqueous solution. Different morphologies of the LiMnPO 4 were obtained by the solid-state reaction of the precursor with LiOH (granular, 100–300nm) and by ion-exchange reaction with eutectic mixture LiCl–LiNO 3 (flake-like crystallites up to 10μm). The morphology and size distribution of the precursor NH 4 MnPO 4 ·H 2 O is preserved during ion-exchange, establishing a new preparation route for nanosized LiMnPO 4 . After ball-milling with carbon black the granular material delivers 30% of the theoretical capacity at C/5. The rate capabilities of the obtained materials are compared with the results from sol–gel synthesis in the light of particle size effect.