Global climate change will cause changes in coastlines, the boundary between land and sea. Polar regions have the largest glaciers, and melting of these glaciers could lead to rapid changes in coastlines throughout the world. Therefore,research on polar coastlines is important. Satellite images can be used to determine the coastal water boundary line. In this paper, we investigated the coast of Greenland using the Gamma filtering method for speckle preprocessing of Synthetic Aperture Radar ( SAR) data. We present a method combining the Support Vector Machine (SVM) and the Canny edge detection operator to extract the coastal water boundary line. Using this approach,the extraction accuracy of the Greenland coastline from TerraSAR-X images was up to 60 percent.