Desulfurobacterium thermolithotrophum is a species of autotrophic, sulphur-reducing bacterium isolated from a deep-sea hydrothermal vent. It is the type species of its genus, being thermophilic, anaerobic, Gram-negative, motile and rod-shaped, with type strain BSA<sup>T</sup> (= DSM 11699<sup>T</sup>).