Abstract: The R^*-tree can improve the processing efficiency of unorganized point clouds and surface meshes.To increase the space utilization of R^*-tree nodes, the node splitting of R^*-tree is regarded as a multi-objective optimization problem which can be solved by using the genetic algorithm to obtain the approximate global optimal solution sets.The optimal solution is chosen based on the overlap degree and volume of the nodes' minimal bounding rectangles, and then the best node splitting of R^*-tree is achieved.Experiments show that the algorithm can solve the node splitting problems for any complex geometric objects and improve the R^*-tree spatial query efficiency with few parameters.