Based on the ecological footprint model and considering the major influence of import and export trade on regional ecological footprint and biocapacity,this paper constructs a nonlinear dynamic model for ecological footprint,biocapacity and foreign trade.Research results show that:(1) in a regional equilibrium state，there is a linear relationship between ecological footprint and biocapacity,which proves Mathis Wackernagel′s point in a way;(2) the increase of a regional maximum biocapacity will induce the increase of equilibrium ecological footprint and biocapacity,which indicates that to increase every kind of productive and ecological land area by protecting environment,controlling building land,strengthening land management,etc.,and to raise per unit regional output through science and technology,cash invesment,management,etc.can not only improve biocapacity,but also directly influence the scale of ecological footprint; (3) maintained the ecological footprint of per unit trade is bigger than the ratio of maximum biocapacity to maximum ecological footprint shouid be for the sustainable development in a region or country.That means to import more natural-resourced primary bio-products and less technical products with high additional value and luxuries(eg.,car).As a matter of fact,exporting nature-resourced primary bio-products is to export biocapacity,thus we should enlarge the export of those invisible social resources,such as human resources,science and technology,management,education,ect.; 4)rational trade structure and independent innovation are vital to regional sustainable development.