The degradation of petroleum hydrocarbons by plant-microbial associations, as well as the peculiarities of the interaction between microorganisms in consortium and the associated plants, have been studied. It was shown that degrader microorganisms that are part of the consortium Rhodococcus erythropolis S26, Acinetobacter baumannii 1 B, Acinetobacter baumannii 7, and Pseudomonas putida F701 were effective in the degradation of oil and were good colonizers of plant roots (barley). The efficiency of oil degradation increases when microorganisms and plants are used together.