Inflatable antenna structures made of flexible membrane materials have many benefits over machine deployable antenna： low in mass and can be packaged into small volumes and are easy to control the deploy process. A kind of ground demonstration model of lenticular membrane antenna was designed in this paper, and nonlinear finite-element analyz model of inflatable structures is built. Precision analyses of inflatable reflector were conducted, and all important design parameters such as inflation pressure, membrane thickness, material characteristics and antenna focal length are investigated. The parametric study results were then used to design a 2-meter ground demonstration model of lenticular membrane antenna. The demonstration antenna reflector model was assembled by twelve gores from 0.18-mm-thick Mylar films. Gravity influence in the reflector was compared under three postures and one of them is chosen as final experiment posture. For this antenna structure, a new feasible shape adjustment measure was improved based on surface accuracy test of the membrane antenna reflector. Analysis and experiment results indicate that this method can improve the inflatable reflector precision effectively.