As Landscape changes have been the most significant feature of the coastal wetland, we focused on the core area of Yancheng Nature Reserve in the research. Basing on the type of landscape change, we divided this area into two parts: change in the northern area which was characterized as from human activities, and that in the southern area characterized as from natural causes. Using remote sensing digitized data from 2000, 2006 and 2011, and applying GIS techniques and methods of landscape ecology, we analyzed the differences between the temporal and spatial changes in landscape pattern caused by natural and artificial reasons. The result showed us that from the following three aspects. Firstly, in the District by human activities, from the year 2000 to 2011, the area of S.alterniflora marsh increased from 272hm² to 781hm²; the average dimension tended to decline while the polymerization index showed an increasing tendency, which means the S.alterniflora marsh tended to gather in space and to be regular in pattern form; the growth rate of S.alterniflora marsh first appeared quick and then slow. In terms of spatial landscape evolution, the S.alterniflora marsh extended in both seaside and landside, with its width increasing from 598.679m to 1719.002m. Secondly, in the District by natural processes, from 2000 to 2011, on one hand, the area of S.alterniflora marsh increased from 20230hm² to 39740hm². On the other hand, the average dimension and polymerization index appeared a decline trend after initial ascent. And thus, the growth rate of S.alterniflora marsh was stable at the speed of 160-180 hm²/a annually while the coastline increased 15hm²·km^-1·a^-1 per unit length annually. By comparison, during 2000 to 2011, the growth rate of S.alterniflora marsh in natural wetland district was higher than that in the manual management district. In terms of spatial landscape evolution, the width of S.alterniflora marsh increased from 1625.586m to 3193.317m, as it extended to seaside direction from 2000 to 2006 while in both seaside and landside directions from 2006 to 2011. Thirdly, by natural processes, the expansion of S.alterniflora marsh was influenced by the climate, geomorphic processes, hydrological processes, vegetation pattern and competition between species, as a result, it appeared strong zonal characteristic. By human activities, the ecological process changed as the expansion power of seawater was affected,with the dam being blocked.Consequently, the ecological system evolved towards the freshwater wetland and furthermore it restrained the expansion of S.alterniflora marsh, which present inlay pattern to a certain degree.