Yeast Rhodosporidium toruloides was isolated from soil contaminated with petroleum hydrocarbons from Vellore, India. Yeast strain showed 99% sequence similarity with Rhodosporidium toruloides. In vitro study to check the efficiency of indigenous yeast to degrade hydrocarbon present in diesel oil was done in shake flask. Isolated yeast was enriched in mineral salt media containing diesel oil as sole source of carbon. It utilized hydrocarbons present in diesel oil efficiently. Degradation was preliminarily determined by change in physical appearance of medium viz., colour and viscosity. Degradation of hydrocarbons present in diesel oil was further confirmed by gravimetric analysis and gas chromatography. Residual oil after 15 days of degradation period was quantified gravimetrically and subjected to gas chromatography with flame ionization detector analysis. Chromatogram obtained after GC analysis clearly showed degradation of hydrocarbons present in diesel oil. © 2011 Academic Journals Inc.