The aromatic hydrocarbons were investigated by high resolution of gas chromatographymass spectrometry of nine crude oil samples from a number of producing wells in the North Western Desert and South Gulf of Suez. A series of molecular indicators of benzothiophenes and dibenzothiophenes were utilized to recognize the significance and their applications in identifying the source depositional environments and maturation of crude oils. The results showed that the studied crude oils were derived from silici-clastic source rocks (Salam-3, El Kharita-1, Zeit Bay-2 and Gemsa-SE oils), and crude oils were derived from carbonate source rocks (Kahraman-1, Tut-1, Meleiha-4, Yasser-1, and E. Esh El Mellaha wells). The maturity parameters 4-MDBT/1-MDBT and 2-+3-MDBT/1-MDBT ratios indicate that the studied crude oils were originated at advanced levels of thermal maturity. Therefore, aromatic hydrocarbons have a powerful way to infer crude oil source rocks depositional environments and maturation.