According to the error caused by imperfect direct distance ranging technology in static networks, an improved Voronoi graph localization algorithm based on geometric constraint is proposed. The Cayley-Menger determinant is introduced to limit the distance relation, and the constraint equation of distance error is obtained, and then the optimal problem is solved by using the Lagrange multiplier method, the distances between nodes satisfy the true geometric constraints after the optimization. At the same time, the distance information is applied to the location of many anchor nodes. At last, the modified distance is applied to the Voronoi map positioning algorithm to optimize the algorithm. Simulation results show that the proposed algorithm is superior to the traditional positioning algorithm based on Voronoi map, which can effectively improve the success rate of positioning and positioning accuracy, and it has wider application scope.