Data are collated on the distribution of hydrocarbons, metalloporphyrins, and sulfur-containing compounds in oils of the Vymskii (Aalenian) and Malyshevskii (Bathonian) horizons from the Middle Jurassic oil-and-gas bearing basin in Western Siberia. It was shown that these oils are characterized by wide variations in the alkane composition and the contents of thiophenes, sulfides, disulfides, mercaptans, metalloporphyrins, and perylenes. The amount of sulfur-containing compounds in Middle Jurassic oils of Western Siberia is inversely proportional to the pristane/phytane ratio; the higher the ratio, the higher the content of sulfides and the lower the: content of thiophenes.