On the basis of characteristics of high precision projection objectives, a kinematic mount apparatus was proposed. In order to evaluate the performance of the kinematic mount apparatus, the geometrical deformation and the optical surface figure reproducibility of a lens caused by the kinematic mount apparatus were investigated with Finite Element Method(FEM) and experiments. Firstly, the working principle of kinematic mount apparatus was introduced and the analysis method for surface deformation was also given. Then, surface deformations from the experiment and the finite element analysis were fitted with Zernike polynomials and obtained results by the two methods were compared for verifying the feasibility of the FEM. Furthermore, the optical surface deformation of the lens caused by the kinematic mount apparatus under the gravity was also explored. Finally, the reproducibility of optical surface figure of lens during a repeating assembly of the kinematic mount apparatus was also given with the experiment method. The experiment and FEM results indicate that RMS values caused by clamping force are 1.004 nm and 0.973 nm, respectively, and that induced both by clamping force and gravity are 2.538 nm. Moreover, the Power, Pre Trefoil and Sec Trefoil are the main aberrations of surface deformation, and the optical surface figure reproducibility of lens is 0.645 nm during the repeating assembly. These results mean that the kinematic mount apparatus can keep the optical surface figure in a good reproducibility.