Electric propulsion technology is an innovative power technology that is efficient and environmentally friendly. However, this technology is limited by the development of battery, making it difficult to meet the needs of the aviation field. The hybrid electric propulsion technology provides a feasible solution to this problem. Based on the rule-based series–parallel configuration, a hybrid electric propulsion system configuration for helicopter is proposed. The simulation model is built by MATLAB. Through the analysis of the simulation results, it is concluded that this configuration is reasonable and can reduce fuel consumption rate and improve the endurance of the helicopter to a certain extent.