Abstract: Cluster V_nP_m⁺ generated by laser plasma reaction have been studied using quantum chemistry ab initio method. Possible geometric structures are examined and optimized. For VP_m⁺,vanadium atom tends to combine with two phosphorus atoms to form planar systems, and VP₄⁺ and VP₆⁺ are more stable of them. There is one growing helices for V₂F₄⁺~V₂P₈⁺, the number of phosphorus atoms between 2 vanadium atoms grow from four to eight, and these phosphorous takes the shape of tetrahedron, pentagon, octahedron or cube.... It’s found that in many-vanadium phosphide V_aP_b⁺ and V_bP_a⁺ are of the same structure, which may be rationalized by the fact that V and P have the same number of valence electrons.