Mycobacterium sp. C2-3 was isolated from petroleum contaminated soil around an oil reservoir and identified by analysis of its 16S rRNA gene sequence, Strain C2-3 was able to use fluorene, phenan-threne, fluorathene and pyene as sole sources of carbon and energy, yet unable to geagrade naph-thalene, The strain was also able to use n-alkanes, such as hexadecane and heptadecane, and phenanthrene and pyrene, in particular, were degraded rapidly,. The phylogenetic data suggested that the isolate C2-3 is a thermosensitive, fast-growin strain of Mycobacterium sp.