Abstract: How to improve the stability and accuracy of the algorithms for point clouds splicing was studied, and a hybrid positioning point clouds pre-splicing algorithm based on least square method was advanced, and the detailed algorithm was given, and a precise algorithm based on total least squares method was presented, and the optimization of existing ICP algorithms was achieved, and the global convergence and the stability of the algorithm were ensured, and the number of iterations was reduced, and the accuracy and efficiency of the algorithm was improved.