Polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) contents in marine sediments, which were sampled at 21 stations from the southeastern coastal areas of Korea in February 2000, were analyzed using high resolution gas chromatography coupled to mass specetrometer (HRGC/HRMS). The concentrations of these contaminants ranged from 44 to 855 pg/g dry weight and I-TEQ concentration varied from 0.6 to 8.6 pg/g dry weight for the investigation stations. The highest concentrations were found in sediments of Pohang coast. Examination of the homologue groups showed that octachlorinated dibenzo-p-dioxin (OCDD) and heptachlorinated dibenzofurans (HpCDFs) were predominant homologues in Busan, Jinhae and Ulsan coasts, whereas pentachlorinated dibenzofurans (PeCDFs) were dominant species in Pohang coast. In particular, the dioxin contribution of Pohang coast may be attributed to combustion process of the same point source. The investigation of the homologue profiles using cluster analysis indicated that there may be different dioxin sources in the studied stations. The relationship between the contents of PCDDs/DFs and the percentages of TOC in marine sediments was discussed.