In this study, bioremediation of an Egyptian oily sludge polluted soil with total petroleum hydrocarbon content of 53,100 mg kg(-1) was achieved on a microcosm level at 30 degrees C over a 180-day period. The analysis of variance revealed that soil microcosms biostimulated with corn steep liquor and bioaugmented with Micrococcus lutes RM showed significant removal of total petroleum hydrocarbon relative to natural attenuation microcosms; recording total petroleum hydrocarbon removal of 44 and 54% with p = 0.004 and p = 7.69e-5, respectively. Kinetic study revealed that the degradation processes followed the first-order model. Bioaugmentation microcosms showed also the highest biodegradation efficiencies on different total petroleum hydrocarbon fractions: saturates, aromatics, resins, asphaltene, and the highest soil heterotrophic activity as measured by accumulative evaluation of CO2.