Abstract: The grid integration of high proportion of renewable energy makes the distribution network increasingly dependent on the communication system. To reduce the influence of communication equipment fault on the operation of the distributed control system, an optimal control method for distributed generator（DG） groups losing communication in the distribution network considering multiple communication faults is proposed. Firstly, the communication link matrix of the distributed communication network is established, and the typical fault scenarios are obtained based on the communication link search. Secondly, considering the uncertainty of communication fault scenarios, source and load, a double-layer optimization model of DG groups losing communication is established to minimize the comprehensive risk. The outer layer of the model optimizes the multi-scenario control strategy of DG losing communication, and the inner layer of the model optimizes the control strategy of other DGs. Finally, the improved particle swarm optimization algorithm is used to solve the optimal control strategy of the control nodes for the DG group losing communication. The effectiveness of the proposed control method is verified through an IEEE 33-bus case system. The results show that the proposed method can effectively reduce the system operation risk and improve the power supply reliability.