In terms of different points of view in the strategic choice of Yangtze Delta tourism development, this paper makes a statistical analysis on such indicators as city tourism importance degree, regional tourist income primacy degree, regional tourist income concentration degree and city tourism economic density, by the use of data on tourist income and GDP of all Yangtze Delta cities in economic and social development over the years from 1999-2000. It exploites Gini Coefficient approach to measure the evenness of social income distribution from economics, thus finds that there is a decrease in its regional tourist income primacy degree and concentration degree, an increase in tourism primacy degree of all cities except Shanghai, a prevalent increase and growing approximation among tourism economic densities of all cities, reveals decentralization and homogenization of tourism economy of Yangtze delta city group, and further analyzes the cause of dynamics. Based on these tendencies, tourism development strategy of Yangtze delta should be to transfer from ring model centering on Shanghai to polycentric networked model and give priority to the development of waterscape resources, tourism diversity and ecotourism as well.