With the transformation of China's economy and social development, the issue of spatial expansion of the urban construction land and its driving forces has drawn extensive attention from both academic researchers and government departments. The analysis from the perspective of mega-events driving forces is firstly adopted in this paper, to take Taizhou metropolitan area in Jiangsu Province as a case study, which is a representative in the Yangtze River Delta in China's urbanization process. Remote sensing interpretation data of Landsat TM, and ALOS which represent main years' images of Taizhou metropolitan area within the last 20 years are used in the analysis. From the perspective of mega-events driving forces, statistical analysis, together with remote sensing, geographic information system methods and procedure analysis, is adopted to analyze the spatial expansion of urban construction land in Taizhou metropolitan area. The main conclusions are: the mega- events driving forces play an important role in spatial expansion of the urban construction land. In different periods the driving forces of spatial expansion of the urban construction land are significantly influenced by the national, regional and urban mega-events. For the last two decades, the dominant patterns of Taizhou metropolitan area urban construction land, in terms of spatial expansion, are spot-filling and extension, as well as transformation, point-axle corridor pattern, and satellite city pattern, which jointly form an net expansion pattern. The temporal expansion, however, is characterized by rotating development between the south and the north districts, and between urban districts, rural villages, and port regions along the Yangtze River. No research on such issue before was from the perspective of the mega-events driving forces, so this is the academic innovation in this paper. The expansion of city construction land and its driving force has drawn extensive attention from both academic researchers and government departments as Chinese state council focuses greatly on urban construction land management. The discussions of the management are required from theoretical researches and real applications. From an original perspective of mega-events driving forces, this paper takes Taizhou metropolitan area in Jiangsu Province as a case. Not only extracting methods and techniques of urban land-use information with serial high spatial resolution in the background of multi-source data fusion and integration are solved in the research, but also basic spatial information for further study of urban sustainable development in the Yangtze River Delta is provided, with the special period background of Jiangsu Province's great development along the Yangtze River and notable ambition of the modernization in eastern China. Taizhou metropolitan area is selected as the case in our study for the following two reasons: On the one hand, Taizhou metropolitan area, located in the Yangtze River Delta agglomeration, is in the progress of rapid urban construction land expansion; on the other hand, the typical characteristic of Chinese urban construction land expansion is presented in the case: point-axle corridor pattern and net pattern — the northern part of Taizhou metropolitan area shows spot-filling and extension pattern in low density filling; the middle and southern parts of that display point-axle corridor pattern, and satellite city pattern, which jointly form an expansion net pattern in high density filling. International scholars researched on this issue mainly from the perspective of geography and economics. Urban spatial expansion can be categorized into five types: infilling, outspreading, linear development, extension, and large-scale projects (Roberto,2002)