Abstract: No-vent storage technology is often applied to store the expensive gas and the ultra-high-purity gas in cryogenic vessels.The effective prediction of pressure is critical for ensuring system security and realizing the no-vent storage.The pressure and temperature of liquid xenon for no-vent storage were predicted based on the homogeneous model that assumes that the temperature of the gas phase and the liquid phase are the same and the pressure of the vapor is the saturation pressure at the corresponding temperature.For further optimization of this model,the heat leak was considered as a function of real-time temperature,and the thermal inertia of the inner tank made of SS304 was taken into account in the present paper.Based on the model,the no-vent storage of liquid xenon in more than 400 days was simulated for the cryogenic tank with a volume of 6 m³and a storage capacity of 6 000 kg xenon corresponding to an initial filling rate of 34%,and the variations of the pressure and temperature were calculated.It was concluded that the storage time increased by 31.9%due to the thermal inertia effect of the inner tank.