T-tube is widely used in aeronautics and astronautics, pipeline, petrochemical, light industry, automobile, life supplies and so on. The forming process of T-tube is non-symmetric deformed and the material deformation laws are very complicated, so it is quite difficult to machine a produce. In this paper, based on the software ABAQUS, the numerical simulation model was set up and then the high-pressure and axial feeding bulging process of T-tube was simulated. It was analyzed that the main process parameters, such as internal pressure, axial feeding and central punch displacement, had influenced the tube forming quality. The research results show that: (1) The wall thickness of branch becomes thinner and the height of branch does not increase higher in the forming process. (2) With the increment of axial feeding displacement, the wall thickness of tube becomes thicker and the height of branch becomes higher quickly. (3) At the pressure of 110MPa, the wall thickness at the top of branch becomes thinner gradually with the increasing distance between initial position of central punch and tube. (4)When the friction coefficient of surfaces was 0.06 and the ideal branch was produced, the proper parameters of axial feeding bulging processes are as follow: the internal pressure is from 110MP to 120MP, the axial feeding displacement is 14～16mm and the distance between central punch and main tube is from 0mm to 4mm.