Abstract: The end section storage is an important mean for short term peak shaving of gas pipeline. Steady state calculation is usually adopted to estimate end section inventory, however the process of end section storage is a complicated dynamic process, and the end section inventory obtained by steady state calculation has some deviation. The deviation range of steady state calculation is defined via dynamic simulations on end section storage in many conditions. And some patterns involving end section storage are obtained. According to the factors which affect end section storage of gas pipelines, six conditions which have different inner diameters, lengths, inlet pressures, and flow rates of end section are simulated by using an internationally popular pipeline simulation software of Stoner Pipeline Simular (SPS) 9.6. The simulation results indicate that with dynamic conditions, end section inventory obtained by steady state calculation is about 14%—25% less than that by dynamic calculation. The change of end section inventory is affected by the change pattern of end point gas load, the largest end section inventory occurs nether before the largest end point gas load or more or less at the same time. When the end point flow rate changes, end section inlet pressure changes after outlet pressure. The longer end section is, and the larger inner diameter is, the more obvious hysteresis is.