Biogas purification and separation membrane system makes it possible by increasing calorific value of ordinary biogas.The quality level of pure biogas is similar to vehicle fuel.In this paper,decarburization separation membrane unit is the key components of biogas separation and purification membrane system.The unit consists of membrane housing and hollow fiber membrane core.The membrane housing structure design parameters are based on both the design parameters of hollow fibre membrane core and the design method of pressure vessel according to steel pressure vessels standard.The housing 3-Dimension model was constructed on the basis of the design parameters of the housing using Simulation in Solidworks.Then the housing structure finite element analysis was carried out according to the simulation experiment in the different pressure condition.The experimental results showed that,using optimization housing design parameters,the housing of decarburization separation membrane unit was made and experimental device was assembled with membrane core and other parts of the system.The structure and parameters of experimental device can meet the requirements of work condition.