On the basis of the high-resolution elevation and grain size data collected from intertidal flats at Jianggang (Jiangsu) coast, we distinguish the geomorphic response of accreting intertidal flat to reclamation, and also proposed a conceptual model. The results show that reclamation at upper accreting intertidal flat with sufficient sediment supply could result in fast fine sediment accumulation outside the sea wall. However, sedimentation rates and sediment grain size parameters change none significant far from the sea wall. The upper intertidal flat changes into low energy status due to the sea wall construction, which results in sediment accumulation with a maximum sedimentation rate. Thus, the convex point of tidal flat profile would move towards sea wall and then a dual convex profile could develop. In addition, large-scale tidal creeks and their migration are important factors changing the profile shape of intertidal flat. In the future, the long-term evolution of intertidal flat due to sea level changes is required the long-term climate change study.