Abstract: A hydrocarbon?degrading and biosurfactant?producing bacterium was screened out from contaminated soil in Tarim oilfield. The bacterial strain named BIT?BS001 was identified as Rhodococcus equi. by the morphology, physiology?biochemistry experiments and 16SrDNA sequence analysis. The optimal temperature, pH and salinity values for its growth were 40℃, 7.0 and 2%, respectively. Also, BIT?BS001 was able to germinate at 55℃ utilizing the crude oil or paraffin as the sole carbon source, and by which the degradation rate of crude oil could reach to 62% and paraffin to 37% in 50 h. Analysis of crude oil degradation by GC suggested that the crude oil composition and physiochemical property were changed and improved. The biosurfactant produced by BIT?BS001 was primarily identified as rhamnolipid based on IR and HPLC analyses, by which the surface tension could be decreased from 61.0 to 30.1 mN/m in fermented liquid medium,with the efficiency of oil displacement of 74% based on the physical model experiments. The composition analyses indicate that the BIT?BS001 bacterial strain has a good application prospecting in both microbial enhanced oil recovery (MEOR) and polluted environment biore?mediation