Metabacetus hermani new species with type locality Vietnam, Hatinh Pr. is added to the six previously described in the rarely collected genus Metabacetus Bates (Carabidae: Abacetini (contained in Pterostichini auct.)). A key to adults, incorporating all species and subspecies of the genus is provided. Characteristics of the members of this genus and species of other genera, e.g., Tiferonia Darlington, Mateuellus Deuve, and Cosmodiscus Sloane and Abacetus Dejean, suggest that Metabacetus is a taxon in the basal grade of a clade including all of these genera. Metabacetus vandoesburgi Straneo is newly recorded from Sabah, Malaysia making it the only species in the genus known from outside its type locality.