LiFePO_4 materials are prepared by hydrogenous reduction(a method of preparing LiFePO_4 material with prue H_2 gas as protective and reducing gas) with FePO_4·2H_2O.The samples are characterized by X-ray diffraction (XRD),scanning electron microscopy(SEM),cycle voltammetry(C-V) and electrochemical performance testing. The results show that materials with a single olivine structure,rules of the sample morphology and particle uniformity. It has a lower post-impedance,and higher initial discharge capacity after coated with carbon and magnesium-doped (LiFePO_4 125.09mA·h/g,LiFePO_4/C 139.17mA·h/g and LiMg_(0.01)Fe_(0.99) PO_4/C 146.97mA·h/g).