Abstract: Considering that the earthing pressure and concentrated stress of the top beam of the conventional steel advanced support in contact with the rough surrounding rock are high, which has a great influence on the support efficiency and tunneling efficiency of the advanced support, a kind of airbag advanced support top beam mechanism is studied.The air bag method is used to realize the variable stiffness support function of advanced support, and the distributed variable stiffness airbag element is used to form the supporting mechanism of the advanced support top beam.The general finite element software ABAQUS is used to simulate and analyze the support characteristics of the top beam support mechanism of the airbag advanced support proposed in this paper: when the steel top beam is in contact with the rough and uneven surrounding rock, the contact area between the steel top beam and the surrounding rock is small, which will produce greater stress concentration, while the airbag top beam support mechanism can produce deformation when contacting the roughness uneven surrounding rock, so as to increase the contact area and avoid stress concentration.The airbag advanced support top beam support mechanism can increase the contact rate between the advanced support top beam and the surrounding rock by more than 40%,and reduce the contact load by more than 60%,so that the grounding specific pressure of the advanced support top beam can be controlled in a reasonable range, thus improving the reliability of the advanced support top beam support mechanism.