Abstract: With Pukou District of Nanjing as an example, the article introduces SLEUTH cellular automaton model and adopts the Landsat TM/ETM+ remote sensing data in five study periods(the years of 1988, 1995, 2000, 2004 and 2008)to simulate the general situation of urban expansion of the study area with or without the planned cross-river channels.And the influence of the planned cross-river channels on the urban growth of riverside city is analyzed from the perspective of quantity increase of construction land as well as spatial growth.The research shows that:1) SLEUTH model, after adjusted and tested, could well simulate the quantity growth of construction land as well as its characteristics of spatial distribution in the study area, therefore, it could be fairly applicable to the research of urban expansion of the study area; 2) the construction of planning cross-river channel has a significant impact on accelerating the growth of riverside city, but its driving effect will gradually decline year by year.The newly increased construction land in the study area will rise by 48.05% and 62.33% in 2020 and 2030, and the contribution rate of planned cross-river channel is 20.67% and 17.50%, with a decreasing driven effect year by year, which is particularly significant in the street of Jiangpu, Dingshan and Yanjiang in "Pukou New Town".