A method of an oil spill detection system is discussed which provides reliable, economical, optical, noncontact, hydrocarbon pollution detection technique. System uses the fluorescence wave crest around 360nm as the character of oil spill on the water, which is found through the fluorescence spectra of lubricating and diesel oil detected through experiments. A proto type is designed and tested. The error which is linearly proportional to the distance can be reduced by moving average. System achieves Micron-level sensitivity for a comprehensive range of oils and can detect hydrocarbon releases in real-time. This system can be used for containing and preventing accidental discharges of hydrocarbon-based pollutants and making early warning of pollution before the environment are damaged. It is a great progress in the study of oil spill detection field.