Porous LiMnPO4/C composite nanofibers between 150 and 250 nm have been synthesized as a cathode material for lithium ion batteries via electrospinning. The porous LiMnPO4/C composite nanofibers show excellent electrochemical performance including a high reversible capacity of 112.7 mA h g(-1) at 0.2C, a stable cycle retention of 95% after 100 cycles at 1C, and excellent rate capability (73.1 mA h g(-1) at 5C) in constant current mode between 2.0 and 4.5 V. These improved electrochemical properties are attributed to the one-dimensional geometry and porous structure, which significantly enhanced kinetics associated with electrons and Li ions.