The dynamics of dehydrogenase activity in a southern chernozemic oil-contaminated soil during natural attenuation and by using two remediation techniques (stimulation of an indigenous microflora and introduction of active oil-oxidizing Dietzia maris strain AM3) was examined in laboratory experiments. It was shown that dehydroge nase activity expediently use to estimate the initial bioremediation processes and for monitoring the remediation process by bioaugmen tation.