Aiming at the requirements of large load, high stability and long deployment distance of the secondary mirror deployment mechanism for space camera, a high stiffness and high precision 6RRRRR deployment mechanism is proposed. Based on the screw theory, the basic configuration of single-freedom deployment is analyzed. Based on the single-freedom deployment configuration, a scheme of multi-bar tilt circumferential uniform distribution and cable tension is proposed, and the fundamental frequency analysis is carried out, the optimal configuration of deployment stiffness in the application scenario is obtained. On the basis of the optimal stiffness configuration, a three-step deployment driving method is proposed. Based on the Lagrange equation, the dynamic model of single-step deployment is established, and the driving torques of the two schemes with the driving angle arranged at the root hinge and the middle hinge are calculated respectively, and the best driving scheme is selected. Finally, the accuracy analysis model of the 6RRRRR deployment mechanism is established, and the eccentric tolerance, tilt tolerance and axial position tolerance of the upper platform are calculated. The above research can provide a reference for the design and analysis optimization of large space deployment mechanisms.