Coastal is an area that is influent by two processing factors that are marine and land dynamic process. In this area, occurs a complex dynamic process, which caused the relatively quick changes. The use of remote sensing data to study the process that occur in the area will get some helpful information to know the changes that happened, e.g. to study coastline dynamic. The need of this kind information is useful by countries that have long coastline and have so many islands just like Indonesia. This study use Landsat 7 data with ETM+ sensor, supported by Landsat 5 (TM), bathymetric map and tidal data from the study case area of Riau Archipelago especially Batam Island and surrounding. From this study can be summarize that the information on the coastline can be obtain in easy and accurate with combining band ratio of 4/2 and 5/2. The result has to be corrected with visual interpretation of color composite 543 RGB by visual editing to reduce errors from digital processing. The result also has to be corrected with tidal data because the information are obtain from different tidal time, which are usually different with the standard tidal data that are used to determine the coastline.