According to the requirements of light weight and high stiffness of deep space exploration camera, an ultra-light main support structure was designed. The deep space exploration was more severe than the earth exploration environment. As the main bearing structure, the main supporting structure should have high stability in launching and orbiting to keep the relative position between the optical components. In contrast to traditional methods, topology optimization was used to obtain optimal load path with clear topological results of the main support structure, and then the fundamental frequency of the main support structure was improved by size optimization. At last, the lightweight design was adopted, and the weight reduction rate of the front and rear frame structures was over 90%. The results of finite element analysis and test show that the integrated main supporting structure can meet the requirements of tolerance and the basic frequency(80.264 Hz) is much higher than the requirement of 1st frequency of satellite. The method of applying optical measurement has a tilt angle of 3″ and 0.3″ relative to the rear frame before and after the vibration, which satisfies the tolerance requirements of the optical system and has good stability. The wavefront aberration of the system after a large number of mechanical experiments is below λ/14, which satisfies the imaging quality requirements of optical systems.