Spinel LiNi0.5Mn1.5O4 and Fe-doped compound LiNi0.45Fe0.1Mn1.45O4 were synthesized by a wet chemical method combining a solid state reaction process. The comparison from the aspects of crystal structure, surface morphology, charge-discharge characteristics and rate capability of spinel LiNi0.5Mn1.5O4 and LiNi0.45Fe0.1Mn1.45O4 was made. The mechanism of doped Fe was deduced based on the measured oxygen deficiency amount from the TGA experiment. The doped Fe can maintain some oxygen deficiency which makes spinel LiNi0.5Mn1.5O4 contain some Mn3 , improving the rate capability.