A processing method and equipment for achieving arc and milling combined machining was firstly introduced. Then, in order to further verify the feasibility of electrical arc machining (EAM) in the production of aerospace components and its friendliness to subsequent finishing processes, a combined machining of three-dimensional flow impeller sample with complex contour features by EAM Milling and CNC milling was conducted by utilizing a selfdeveloped special machine tool. The results show that the reasonable arrangement of the EAM process can achieve satisfying surface quality while obtaining efficient material removal. The maximum material removal rate (MRR) in EAM was 14500mm³/min. The surface roughness after small energy EAM was R_a12.5μm, and the hardness of the machined surface was 69.4HRB, which had no obvious change compared with the hardness of the substrate. Thus, the surface after the small energy EAM can be well adapted to the cutting requirements, which effectively confirms the friendliness of the EAM process. In the subsequent CNC milling process, the tool wear was small and the state during machining was stable. The surface roughness finally obtained was R_a1.2μm, and due to small cutting allowance, the machining deformation is effectively suppressed. Processing results of the sample flow channel met the design requirements, which fully demonstrates the feasibility of applying the combined processing method to the manufacturing of engine components with complex contour features.