Comparison experimental devices with the different chimney structural parameters for the solar chimney power generation system integrated with seawater desalination have been set up. The performances of these integrated devices have been tested and researched comparatively under the actual weather condition. Results show the seawater regeneration body in the system has certain load range to the flow rate of airflow. It is beneficial to strengthen the seawater evaporation, enhance the freshwater output that the diameter of the chimney is enlarged and the height is enhanced in this range. To the electricity power generation of the system, whether to increase the chimney diameter, or increase the chimney height, the volume of the chimney will be increased when other parameters are fixed, namely the flow rate of airflow will be increased, and the power generation will be significantly increased, thus the solar energy utilization efficiency will significantly improve. In the actual project, it is very important that the optimal combination of different height and diameter of the chimney can be selected according to the actual situation for development of large-scale integrated system. (5 pages)