Abstract: Due to the high active power loss and slow convergence of existing planning methods, reactive power planning including distributed power distribution network based on chaotic sine-cosine algorithm is studied. A mathematical model of reactive power optimization is established in the distribution network, and the chaotic sine-cosine algorithm and iterative search method are used to find the optimal solution that meets the constraints and minimizes the objective function. The optimal solution is output to obtain the optimal reactive power planning scheme. The experimental results show that the active power loss decreases obviously after DG access, and its value is 80~81KW. The active power loss of the distribution network is effectively reduced, and the safety effect of the system is significantly improved. The algorithm in this paper has a faster convergence rate and can approach and reach the optimal solution more quickly. It provides a more intelligent planning scheme for the efficient integration of distributed power sources in energy systems.