Abstract: A mixed bacterial culture was isolated from heavily polluted site in Eastern Region, Saudi Arabia to evaluate the potential for the biodegradation of benzene, toluene, ethylbenzene and xylenes (BTEXs). The isolated bacterial strains in this study could grow in mineral salt medium containing a mixture of BTEXs as the sole source of carbon and energy. The effect of environmental factors such as agitation, incubation temperature and medium pH on the degradation rate of BTEXs was investigated. Substantially, a greater extent of biodegradation of all the BTEXs compounds was observed in stirring liquid culture than in static. As well as, the level of degradation was relatively higher at 37°C than 45°C or 30°C and at medium pH value 7 than 8 or 6 after 21 days incubation. Toluene, ethylbenzene and xylenes were completely degraded by the mixed bacterial culture. However, a bacterial limitation concerning benzene was observed. Results obtained indicate that the mixture of microorganisms present in this study could contribute significantly to bioremediation of aromatic hydrocarbons (BTEXs) pollution.