Аннотация:The results of studying the concentration and composition of hydrocarbons in the suspension of surface water and in the surface layer of bottom sediments in the Kerch Strait in July 2020 in comparison with 2019 and with earlier studies in other regions of the Black Sea are presented. Despite the high concentrations of aliphatic hydrocarbons (especially in the water of the strait (on average 78 μg/L) and in coarse-grained sediments (47 μg/g)), the composition of alkanes did not correspond to the oil composition due to the rapid transformation of petroleum aliphatic hydrocarbons. The factor analysis revealed that the pollution has two sources: the main, pyrogenic (from transport) and, to a lesser extent, the oil one.