Abstract: On the background of practical engineering application, comprehensive research on the effect of bending compliance and equivalent rotation radius dc with different cutout radius r and the minimum section thickness t of the single-axis circular flexure hinge, has been performed through Finite Element Analysis(FEA) by using tested material property. A simplified model which was used to calculate bending deformation of single-axis circular flexure hinge, had also been drawn from series analysis results study. A test setup had been constructed to verify the simplified model. And the difference between calculated value and tested result was within 10%, it indicates that the simplified model can satisfy engineering requirement. Based on the simplified model, a simplified model which was used to calculate deformation of two-axis flexure mirror support structure was proposed, and it can save lots of effort by using traditional theoretical model to design this kind of flexure mirror mount. This model acts as a good reference for the parameter design and size optimization of this kind of flexure mirror support structure.