Oils are complex compounds of hydrocarbons in which carbon and hydrogen are the highest content elements. All oils distinguish based on their physical and chemical properties, which determine their behaviour on sea. When poured into the sea, it passes through chemical and physical changes. Oil pollution can be prevented by preventive measures, however, the possibility of pollution is present always and everywhere. In order to regulate oil traffic and prevent pollution, various international contracts have been adopted by the International Maritime Organization. Once the spill has occurred, it must be monitored and future movements determined in order to organize the equipment and removal personnel in the meantime. The spread of oil stains can be prevented by installing booms and can be removed by the use of skimmers, dispersants, absorbers, incineration or biodegradation. The shores are very sensitive so the removal should be carefully planned. Working machines and a jet of hot or cold water under high pressure can be used or buckets and shovels where machines can’t be used. Collected oil must be properly disposed of for further purification and, if not contaminated, may be re-used.