The hydrocarbon composition of gas condensates sampled from the main producing gas beds of Lower Cretaceous deposits in the Yamburg field was studied by GLC and GC-MS techniques. The trends in the composition of the C-5-C-8 gasoline fraction, normal and isoprenoid C-13-C-30 alkane fraction, biomarker hydrocarbons (steranes and terpanes), C-11-C-13 adamantanes, and C-14-C-15 diamantanes were revealed for condensates occurring at different depths of this multihorizon field. Despite the general genetic resemblance of gas condensates from all Lower Cretaceous reservoirs as found on the basis of HC biomarkers, there are fairly distinct differences in some HC parameters of condensates from beds of various ages, which makes it possible to categorize all Yamburg gas condensates into geochemical groups and subgroups. Judging by the character of variation in the HC compositions of gas condensates along the section of Lower Cretaceous deposits, the formation of Yamburg condensate deposits involved active vertical migration of hydrocarbons from the lower to upper beds.