The effects of clay type, microbial quantity, and inoculation time on the microbial degradation of 0# diesel oil and 180# heavy oil were studied. The results showed that the surfactant-modified clay had a significant promotion effect on the degradation of oil. The removal efficiencies of diesel oil and heavy oil after 7 days were up to 87% and 95%. The optimum conditions were determined and the oil biodegradation was in accordance with the first-order kinetics. All the results obtained can provide experimental basis for oil microbial degradation.