Abstract: The qualitative and quantitative analysis method (GC-ECD) for organic chlorides in naphtha is proposed. Through analysis of different naphtha from different crude oils, it is known that the main organic chlorides in naphtha of domestic crude oils are 1, 2-dichloro propane, methylene chloride, chloroform, carbon tetrachloride, etc. from assistant chemicals used in crude oil production The amount of other kinds of organic chloride is very low. The relative standard deviation of GC-ECD was less than 3.0% and the standard recovery was between 92.9%-103.5%. The results indicate that this method could meet the demand of conventional chromatograph analysis .