This work attempts to substitute V of Li3V2(PO4)3 (LVP) by the doped ion of manganese with the valence of +2, +3 and +4 and various ionic radiuses. A series of Mn-doped LVP composites (LVMP) by different manganese sources are synthesized by sol–gel and heat-treatment. Manganese ion with the valences of +3 and +4 have been successfully inserted into the lattice of Li3V2(PO4)3 to form a stable solid-solution even the substitution mole ratio reaches to 0.2, except the impurity phase of LiMnPO4 in LVMP when manganese ions with the valence of +2 involve in the substitution. Mn2+ exists in all three samples as expected, but the main valence state of Mn ions in LVMP-A, LVMP-B and LVMP-C are Mn4+, Mn3+ and Mn2+, respectively. LVMP-B (MnOOH as dopant) delivers the highest capacity of 137 mAh g−1, than LVMP-A (MnO2 as dopant) 125 mAh g−1 and LVMP-C (Mn3O4 as dopant) 123 mAh g−1. LVMP-B shows the best cycle performance, remaining 98% of the initial capacity after 50 cycles in range 3.0–4.3 V. Mn source of MnOOH properly substituted the structure of LVP enhances the lithium diffusion ability and stability of LVP during charge/discharge.