Mollusks of the genus Galba Schrank, 1803, inhabiting north-east Africa and the Arabian Peninsula, are separated into two morphologically distinct groups. The first group contains two conchologically indistinguishable species, G. truncatula (O.F. Müller, 1774) and G. schirazensis (Küster, 1862). The second group includes one species characterized by significantly larger size and different shell proportions as compared to G. truncatula and G. schirazensis. This species is new one and described here as G. robusta sp. nov. with type locality situated in Yemen. It is hypothesized that G. robusta sp. nov. has a vast distribution, ranging from Central Iran southwards to East Africa. A comparison of the new taxon with two nominal species of Galba, G. mweruensis (Connolly, 1929) and G. umlaasianus (Küster, 1862) described from East and South Africa, as well as some data on conchological variation of African representatives of this genus are given.