In this study, sediment samples were taken at three different points in Edremit Bay at different depths from the sea floor. In Edremit Bay, it was investigated whether the pollution was marine or terrestrial. According the results of measurement of TOC (Total Organic Carbon) values have been yielded results between 10.35-20.36 (Kucukkuyu), 8.14-16.40 (Gore), and 2.71-12.60 g/kg (Dikili) in the marine sediments. The fact that first and second regions are susceptible to mountainous and infra-continental erosion (sedimentation 5.743 and 7.509 mm/year) increased the TOC value. The highest TOC/TN ratio (12.33-46.89) was found in the second region. No linear change in TOC and TOC/TN (Total Nitrogen) ratios was observed at all three points depending on the depth. At results of compared all carotes, the low TOC/TN (2.82-14.48) ratio have been observed in the BH1 carotes, probably the result of small stream beds and low intra-continental erosion. This study shows that TOC and TOC/TN ratios in different parts of Edremit Gulf show inconsistency and this inconsistency arises not only from the marine contribution their natural organic matter, but also from the continent
