The bonds elastic modulus and Poissons ratio have important effects on optical-mechanical simulation of the reflective mirror, but these parameters are influenced by too many factors to accurately obtain.An experiment is conducted to obtain the test mode of the reflective mirror, a finite element simulation is conducted according to the bonds parameters in the Literature［1］ to get FEM mode, and then a correlation analysis is conducted to find that the test mode has a poor correlation with FEM mode.Subsequently, the bonds elastic modulus and Poissons ratio are taken as variables, and an SQP iterative optimization is implemented to obtain these parameters.After model modification, the correlation between the modified FEM Mode and the test mode is significantly improved.Finally, the surface figure and stress of the reflective mirror under two working conditions of assembly stress and low-temperature environment after model modification is compared with that before the modification.The calculation results show that, after model modification, the change of surface figure resulted from assembly stress will have influence on optical imaging, and the problem of stress under low temperature cant be ignored.