In order to compensate the optical system bias, which is caused by the change of elevation angle and thermal gradient during the optical alignment of the telescope, a novel high stiffness micro-nano positioning hexapod platform with flexure hinges is proposed in this paper. The novel flexure hinge has a mechanical limit, and its equivalent model is established and analyzed. In addition, in order to speed up the solution process, a novel simplified inverse kinematic model is developed based on the rigid body kinematic theory. Then, an effective rigid-flexible coupling simulation system is built to verify the correctness and applicability of the inverse kinematic model. Finally, a systematic experimental test method and a statistical-based data analysis theory are proposed. The experimental results show that the resolution and repeatability of translation and rotation and lateral stiffness are as follows: 0.3 mm and 0.5 arc sec, ± 0.5 µm and ±0.5 arc sec, 131.6N⋅µm-1 and 133.0N⋅µm-1. The proposed hexapod platform can be used to correct the optical system bias of large-aperture telescopes.