Abstract: The steam generator in the Solar Two molten salt solar tower power plant was taken as the research object, the dynamic mathematical model of the steam generator was established based on the conservation equations of mass and energy. Based on the dynamic mathematical model, by analyzing the dynamic characteristics of the steam generator with disturbances at water side and molten salt side, the response curves of the outlet parameters and time constant of the steam generator were obtained. Results show that it takes 205 seconds for the steam generator to reach a new equilibrium after disturbance. However, due to the large heat capacity on the steam side, the response of parameters to disturbance is slow, and the quality of steam affects the safety and economy of the unit. Compared with molten salt, water and steam have higher specific volume and liquid storage capacity, the response speed of parameters at water side is much slower than that of molten salt side.