Abstract: Aromatic hydrocarbons in Sunniland oils and source rocks from South Florida Basin, USA , is analysed, in order to probe into the distribution characteristics of aromatic hydrocarbons and environmental paleoreconstruction. Sunniland oils and source rocks are richer in naphthalenes, phenanthrenes, dibenzothiophenes and triaromatic steroids; and methyldibenzothiophene isomers show V pattern. The relative abundances of fluorences, dibenzofurans and dibenzothiophenes and other geochemical characteristics such as Pr / Ph 1, the even preference of n-alkanes in the region C₂₂-C₃₀, low concentrations or absence of bicyclic sesquiterpanes and abundant aromatic-sulfur compounds indicate that Sunnliandd oils and source rocks were formed under the marine strongly reducing hypersaline environment. Some compounds such as D- ring aromatized 8, 14-secohopanes, long-chain alkylbenzenes and long-chain alkylbenzothiophenes and very abundant extented hopanes (C₃₁-C₃₅) and C₂₄, C₂₆ tetracyclic terpanes suggest that Sunniland organic matter can be related to the bacterial input. Maturity parameters (MPI1, MPI3, MDR4, 1, etc.) indicate that Sunniland oils and sourc rocks are immature to marginally mature.