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Aliphatic and aromatic hydrocarbons have been determined in (28 samples) suspended particulate matter (>0.7 µm) collected at subsurficial seawater and three vertical profiles in a transect from the continental shelf, slope, and deep basin (15 samples) of the western Black Sea. The dissolved phase (<0.7 µm) was collected at subsurficial and in the redoxcline (6 subsurficial and 5 deeper). The highest concentrations of hydrocarbons were detected in the Danube, Dnieper, and Dniester River Estuaries and other point sources of pollution located offshore Romania and Bulgaria where oil production and refining is carried out (i.e., Constantza, Varna). Concentrations of hydrocarbons decreased with increasing distance from the coast, but relatively high concentrations were found at the open stations where the particulate organic carbon (POC) is higher. Fossil PAHs are predominant in the coastal stations, and the unresolved complex mixture (UCM) of aliphatic hydrocarbons is predominantly of a fossil common origin according to the hopane and sterane distribution. The fossil to pyrolytic PAH ratio decreases with source distance attributable to a deposition of pyrolytic PAHs. The spatial distribution of PAHs found in the dissolved phase is evenly distributed. The unresolved complex mixture/ alkane ratio is higher in the dissolved phase and can be attributable to a faster degradation of labile n-alkanes in this phase. Vertical profiles of hydrocarbons in suspended particles show two submaxima located in the biomass maximum abundance and at the redoxcline where there is an enrichment referred to POC due to phytoplankton or bacteria uptake, respectively.