The coastal zone environment is easily affected by many natural and man-made factors, especially improper land use that result in rapid disappearance of coastal sand dunes. In this paper, by using three SPOT images acquired between 2003 and 2009, the change detection analysis of sand dunes and land use show temporal and spatial variability in the costal zone of I-Lan Plain, Taiwan. Based on the results of image classification, the land use/land cover changes and spatial variability was analyzed by using Fragstats, a software for landscape ecological studies. The objectives of this research include: (1) assessment of classification accuracy of two image classification methods; (2) analyzing spatial variability of land-use and sand dunes area; (3) developing a statistical model for illustrating the relationship between land use and changes of ecological environment of coastal zone. It is expected that the results of this study will provide the administration authority with solid scientific basis for strategic decision making on sustainable management of the coastal zones.