Perylene is a polycyclic aromatic hydrocarbon (PAH) that has been found widely in a variety of depositional environments and riverine sediments. It is the most important diagenetic PAH and also produced by in situ degredation of biogenic precursors. Meanwhile, anthropogenic perylene in the aquatic systems could be introduced via terrestrial runoff or airborne particulates and different emission sources. High abundances of perylene relative to other PAHs can indicate origin of the compound. In this study, surficial sediments from Gulf of Gemlik, Turkey were analyzed for special PAH compound ratios, such as Perylene/Sigma PAHs, Perylene/Penta-aromatic isomers, Pyrene/Perylene, Benzo(e)pyrene/Perylene using gas chromatography-mass spectrometry. Having a wide range of concentrations (0.1 to 485 ng/g, dry weight), the highest concentrations of perylene were observed in Gemlik harbour, its anchoring areas, near shore cable and petroleum plants at Guzelyali, close to urbanized towns in the south (Mudanya, Kursunlu and Trilye) and even some resorts areas along the northern coast. High concentrations of perylene relative to penta-aromatic isomers, as detected between 10-75%, indicate diagenetic origin for the presence of perylene. Low level of perylene might have been derived from the anthropogenic inputs, caused by either local effluent or atmospheric dry deposition.