The high speed machining technology of complex surface has been a focus of the study. Based on the analysis of cutting force model for ball-end cutters and cutting force tests of 3-axis machining, the paper brings forward the reasonable oblique angle of tool axis for complex surface with different curvature. According to the different feature of surface shape, the surface is classified in terms of oblique angle formed by tool axis and normal vector of surface. Meanwhile, the processing methods are proposed to adapt to classification of surface. Adopting 3+2 axis method in 5 axis machine to processing complex surface with different features by sub-regional process will effectively improve the surface quality and extend tool life. The paper finally put forward the high speed supplementary processing technology to process the boundary and transition area of surface.