Riparian Lake is an ecotone between aquatic ecosystem and terrestrial ecosystem, and it is one of the most concentrated areas of human activity, consequently, the ecosystem of riparian lake is very fragile. Riparian Lake is one of the most serious degenerative ecosystems because of the disturbance of human activity with the rapid development of economy and society. Poyang Lake is the largest freshwater lake in China and one of the world's important wetland recognized in the Ramsar Convention on Wetlands. There is rich in biodiversity, supporting numerous species of invertebrates, fish, birds and mammals including the White Crane (Grus leucogeranus), Cygnet (Cygnus columbianus), Chinese sturgeon (Acipenser sinensis), and Cowfish (neophocaena phocaenoides). The wetlands provide an important range of ecosystem services; and their protection is an important concern both domestically and abroad. In order to compare changes in the riparian lake landscape, this paper analyzed riparian lake landscape with RS images in four different periods under the same condition of similar water level in 1995, 2000, 2005 and 2010. Changes in landscape spatial pattern were analyzed. Changes in landscape index, area of landscape types, and landscape types were very distinct in the riparian lake, the area of water body decreased more than 100km² in 2010 than in 1995, and the area of vegetation decreased more than 500km² in 2010 than 1995; however, the artificial and bare land increased almost 700km² in 2010 than in 1995. The total Landscape Patches increased, the Largest Patch Area decreased, the Perimeter-Area Fractal Dimension lessened, and Diversity Index of Shannon's and Simpson's increased from 1995 to 2010. Changes of landscape index explained fragmentation level of riparian lake landscape strengthened. Furthermore, the driving force was analyzed according to the historic materials and RS images, the loss of area in water body and vegetation because of the increase of artificial and bare land, mainly sandy soil and urbanization land.