Abstract: The dynamic model of open rack vaporizer(ORV) system was established by using dynamic simulation software. The dynamic response trends of main operating parameters such as natural gas outlet temperature, seawater outlet temperature, seawater inlet and outlet temperature difference, ORV heat transfer capacity and average temperature difference of ORV were studied with changes of disturbance factors such as LNG flow rate, natural gas pipeline pressure and seawater temperature. The analysis showed that the dynamic simulation could accurately simulate the variation characteristics of the main process parameters of ORV with other disturbance factors, and could guide selection design for designers and the safe and stable operation for operators.