In recent years, research on microbial degradation of explosives and nitroaromatic compounds has increased. Most studies of the microbial metabolism of nitroaromatic compounds have used aerobic microorganisms. Ecological observations suggest that sulfate-reducing and methanogenic bacteria might metabolize nitroaromatic compounds under anaerobic conditions if appropriate electron donors and electron accepters are present in the environment, but this ability had not been demonstrated until recently Few review papers exist, and those deal mainly with aerobic bacterial degradation of explosives; none deals with anaerobic bacteria. In this paper we review the anaerobic metabolic processes in the degradation of explosives and nitroaromatic compounds under sulfate-reducing and methanogenic conditions.