As main index of petroleum pollution in the marine organisms n-, iso-paraffins were purified with clean-up method and measured by FID-GC. Ten species of fishes from the near seas of Korea were employed for the study. n-Heptadecane was detected in most fishes. n-Hexadecane and n-octadecane of n-paraffins were highly accumulated in four species of fishes(Seriola quinqueradiata, Sardinia melamosticta, Clupanodon punctatus and Stromateoids argentus), also n-tetradecane and n-hexadecane accumulated in Cololadis saira. Remarkable peak pattern of n-paraffins was not observed in other fishes. Pristane of iso-paraffins was detected in four species of fishes (Sardinia melamosticta, Clupanodon punctatus, Stromateoides orgentus and Cololadis saira).