The deployment property of inflatable membrane tube was studied through experiment under various inflation rates and initial deployment angles in this paper,while the friction caused by gravity was erased by guide track efficiently.The relationships between deployment angle and time,deployment acceleration and time,and inner pressure and time respectively were obtained.The experiment result and analysis showed that the inflation and deployment process were separate,the inflation process could be treated as constant pressure process,and the pressure fluctuation at the folding place wasn't identical with the whole pressure fluctuation.