To solve the problem between limited volume of the rocket mantles and large caliber requirement of antenna and the problem between carrying capacity of rocket and large weight of antenna, the inflatable antenna structure technology is one of the best choices. Afterward, to obtain high precision of inflatable reflector, one of figuration theories which is titled as plan-parabolic reflector, was investigated. The elastic theory analysis was carried out and the relationship between reflector shape and inflatable pressure, material, boundary condition is obtained. There is M shape error between reflector shape and parabolic. Based on these works, the influence that temperature variety affects on the reflector precision on orbit was studied and methods to eliminate this effect are discussed. The analyze result from ANSYS software is compared with the result from this paper and the validity of analysis method is clarified.