Mo-doped　LiFePO4　composite　was　synthesized　by　the　solid　state　method,　using　(NH4)(6)MO7O24　center　dot　4H(2)O　as　the　starting　doping　material.　The　electrochemical　properties　of　Mo-doped　LiFePO4　were　measured.　The　electronic　structures　of　Mo-doped　LiFePO4　were　studied　by　ab　initio　calculations.　With　respect　to　the　density　of　states　(DOS)　of　the　LiFePO4,　in　which　no　electronic　states　are　at　the　Fermi　level,　the　Mo　doping　is　predicted　largely　impacting　the　conductivity.　Experimental　data　of　the　electronic　conductivity　and　of　the　electrochemical　performance　of　Mo-doped　LiFePO4　synthesized　by　a　solid　state　reaction　confirm　the　results　of　the　calculations.　To　characterize　the　doped　LiFePO4　structure　and　the　type　and　the　symmetry　of　the　Mo　sites,　X-ray　absorption　spectroscopy　(XAS)　experiments　were　performed.