Several bacteria and fungi have the property of degrding persistent petroleum compounds and have been extensively studied world wide. In the present study, Proteus sp., was isolated from soil contaminated with petroleum products from Vellore, India. Proteus is well known as an opportunistic pathogen but its role in bioremediation is rarely known. Proteus sp., is gram-negative bacilli belonging to family Enterobacteriaceae. Its potential to degrade diesel oil was studied in vitro using orbital shaker method for 15 d duration. It was able to tolerate 2% v/v of diesel oil. Oil degrading microorganisms were enriched in mineral salt media containing diesel oil as sole source of carbon. Degradation of diesel oil was confirmed by change in physical properties of the media flask, viz. color and viscosity, gravimetric analysis and Gas chromatography. Analysis of results showed that Proteus sp. has capability to degrade diesel oil. Copyright © EM International.