Abstract: In order to improve the system stability of space camera under the force and heat dual environmental conditions, at the same time to achieve lightweight system, high volume fraction SiC/Al composite material with high stiffness ratio and thermal stability has been used in the space camera. According to the integral frame structure, the continuum structure topology optimization based on the variable density method was introduced in the initial design of space camera frame. Iterative solution was operated by setting the corresponding constraints and objective function. The result of topology optimization was obtained under the gravity in X, Y, Z direction. Combining with process requirements, the design of space camera frame was determined finally, and compared with the traditional one. The comparison result shows that the structure stiffness and lightweight ratio of frame structure have been improved after topology optimization. And it helps achieving the design targets of high stiffness and lightweight ratio.