Abstract: Based on three topographical maps of 1935, 1962 and 2005, GIS technology is applied to calculate and analyze coastal evolution, scouring-silting variation and changes of the tidal flat and deep trough of the Xiangshan bay. With hydrological and sediment data of field observation, analysis of the trend of scouring-silting in the study region is carried out in this study. It is of important academic value and realistic value to fully understand scouring and silting characteristics. The analysis results indicate that from 1935 to 2005, the coastline kept stable generally except in some bays and around islands due to reclamation, with its advancing speed 13.8 m/a. As a result, the tidal flat is not completely silting, and the space for deposition of fine sediment tends to decrease. The seabed experiences an adjustment from erosion to deposition, presenting a distribution characteristic of slight scouring near the top of the bay, slight silting near the mouth of the bay and slow silting in the east of the mouth of the bay. Overall, the evolution of the Xiangshan bay is characterized by a slight deposition, and there was an annual average deposition rate of 0.54 cm/a, which can be considered that this is mainly affected by the human activities.