Assumed two processes of town land and ecological protected land expanding to simulate urban landscape dynamic, this paper established an ecological suitability assessment method based on minimum cumulative resistance margin, which can be expressed by using the formula of MCRmargin=MCRecological protected land expansion-MCRurban land expansion.When one pixel’s MCRmargin＜0, it should be divided into eco-appropriate land; Instead, when MCRmargin＞0, it should be classified as the land suitable for construction; and when MCR margin = 0, it should be regard as the watershed between eco-appropriate and construction suitable land. As an example of Xiamen, this paper selected the existing town land and eco-protected land as the sources of expanding, and established a system to calculate resistance from six aspects: terrain, land use, hydrogeology, ecological value, ecological sensitivity, and ecological function. Based on the mentioned method, this paper divided Xiamen into four developmental zones: prohibited, restricted, key and optimized areas, which were 525.3 km2, 455.0km2, 340.8km2, 243.9km2, respectively. The land suitable for eco-protection was 980.3 km2, while suitable for construction was 584.7 km2.