Oil pollution arises in waters near petroleum industrial districts. In oily odor fish caught in the coast near petroleum industries, toluene, other aromatic hydrocarbons and olefinic hydrocarbons have been detected. The authors also reported the presence of organic sulfur compounds (OSCs), probably originating from polluting oil, in fish caught in the Seto Inland Sea after an accidental oil spilling from a tank. In a previous study, the authors detected OSCs in the oyster and mussel caught in the Seto Inland Sea. However, the presence of OSCs and polyaromatic hydrocarbons (PAHs) in sea sediments has not been described. In the present report, OSCs and PAHs in the sea sediments collected in several ports facing Seto Inland Sea were analyzed by a gas chromatographic/mass spectrometric (GC-MS) system.