Based on wind tunnel tests of rigid model, the surface wind pressure t ime series of a huge gas tank were obtained, and the mean wind load and the dyna mic wind load model of the building in frequency domain was established by proce ssing the data. The dynamic characteristics of gas tank were calculated by using the finite element method and the influence of the internal gas pressure on the dynamic characteristics was analyzed. Furthermore, the windinduced displaceme n t responses were evaluated based on random vibration theory. In the mean time, t he influence of the internal gas pressure on the dynamic displacement responses, as well as the deformation of the gas tank were analyzed. The results provide r eferences for windresistant design.