Microbial motility in soil is considered as one of the main obstacles reducing the efficiency of hydrocarbon bioremediation technology. Free living soil nematodes have a strong effect on the transport of seed applied bacterial inoculate mediating colonization of the rhizosphere. Therefore, the aim of current investigation is to evaluate the role of free-living soil nematodes in hydrocarbon bioremediation using a suite of microbiological and chemical methods. A biopile method has been adopted to investigate the ability of free-living nematodes to improve the microbial motility in a hydrocarbon contaminated soil. Enumeration of hydrocarbon-degrading microorganisms was carried out using the Most Probable Number (MPN) technique followed by measurements of soil microbial activity and toxicity. Hydrocarbon concentration was detected by GC-FID analysis. Assessment of hydrocarbon bioremediation showed that the nematode treated biopile was associated with a greater hydrocarbon reduction, comparing with control. This confirms that the addition of soil nematodes to the hydrocarbon contaminated soil had a strong influence on the general soil microbial activity. The overall results of this study concluded that the soil nematodes could play an important role in hydrocarbon bioremediation