Aiming at the network splitting phenomenon in the control process of multi-agent network, considering the influence of informed agent selection on the convergence speed of multi-agents, the pinning control algorithm based on k-shell decomposition is proposed. Firstly, the subnet is divided according to the node connectivity. Then, the method of selecting the informed agent based on k-shell decomposition is proposed. Finally, the pinning control of multi-agent is completed. Theoretical derivation proves that after the algorithm is adopted, the entire mutli-agent network eventually form a connected graph. The experimental results verify that the proposed algorithm can achieve the consensus of multi-agent, and benefits to improve the convergence speed compared with three pinning control algorithms.