With the technology of computer aided engineering, supporting structure of optical reflector of the remote sensor was designed and analyzed. Because supporting structure of the reflector can meet the demands of imaging quality under environment of gravity, but out of tolerance under thermal environment, the supporting structure was improved by weakening stiffness and strengthening flexibility. By modeling, simulating, analyzing the improved structure, and adjusting parameters of flexible structure, the reflector groupware can achieve demand of imaging (PV≤63.2 nm) under environment of gravity. At the same time, the stability of thermal dimension was well. Through dynamic analysis, the structure can not be shaken, fatigued and broken under environment of sin scan and random vibration. Simulating results indicates that surface accuracy of the reflector meets the needs of the imaging quality under mechanics and thermal loads through regulation of flexible structure, and dimension’s stability of structure is better than ever, which shows that the flexible regulating structure is reasonable and feasible.