Abstract: Shengsi Shangchuanshan ocean dumping site was put into service since November 2010, and it received approximately 41.084 million cubic meters dredged materials and provided support for the construction of Yangshan deep-water port. This study aims to illustrate the variation of submarine topography of dumping site and surrounding sea, investigate the effects of dredged materials dumping and discuss the influence factors leading to topographic change. To achieve this aim, the marine topography monitoring data from 2015 to 2017 was used to analyze the topographic erosion and siltation of dumping site and surrounding sea. The results showed that dumping dredged materials had contributed to a certain extent but short-term silting-up in the dumping site and surrounding sea. However, from a long-term perspective, the submarine topography tended dominated by natural process.