Transport aircraft oxygen system was discussed, and a computer analysis model of oxygen system was established in order to analyze the flow and distribution of oxygen in the whole pipeline network. This system was comprised of three parts. They were high pressure oxygen source, aircrew oxygen supply points and cabin oxygen supply points. Separate models were established before the single system. Several special components of oxygen system were created using the external component models in Flowmaster, including the oxygen regulator, pressure reducer and quick-don oxygen mask. It made the designer more convenient to create new system models for different pipeline networksdesign. A computer analysis of the oxygen system was also performed with a given flight assignment using this analysis model,and the simulation results show the oxygen consumption and the flow rate of each oxygen supply points. It was used to verify that the system meets the design reguirements.