Abstract: Thin-walled circular structure are widely used in aeroengine parts, the thin-walled circular parts with large diameter-thickness ratio are easily deformed during clamping and machining, resulting in low quality consistency. In this paper, the deformation mechanism of thin-walled circular parts with features is analyzed mainly from the aspects of clamping method and clamping layout. By establishing finite element model, the deformation of parts under different clamping layout is predicted, and the optimization of clamping layout of thin-walled circular parts is realized. Finally, through the cutting test, the improvement effect of the optimization clamping layout on the machining quality of thin-walled circular parts is verified, he parallelism of the upper and lower end faces and the concentric degree of the inner and outer rings are effectively controlled within 0.02 mm, and the proposed clamping layout design scheme can be applied to the processing of various thin-walled circular parts.