In recent years, many satellites are used for an environmental assessment of the earth and so on, because the observation from the satellite is very available way and noteworthy technique in many fields. This paper reports an application of remote sensing technique for observing and recognizing vessels in wide sea area using image data from the satellite. In order to recognize vessels, an algorithm to search vessels and the system to analyze data are shown. And SPOT HRV data are used for quantitative analysis of marine traffics.