New fossils of Prionogale breviceps found at the early Miocene site of Napak IV, Uganda, at Koru, Kenya, together with a re-examination of the dentition of Namasector soriae from the early Miocene of Elisabethfeld, Namibia, confirm the peculiar morphological combination of these two species which are attributed to the hyaenodont family Prionogalidae. The new material of Prionogale breviceps includes a molariform tooth interpreted as a D4/, the morphology of which differs from the upper molariform teeth previouly known in the holotype maxilla of the species, which can therefore be interpreted as the M2/ and M1/. The implication of this discovery is fundamental for positioning the family Prionogalidae among the Hyaenodonta with two pairs of carnassial molars comprised of m/3-M2/ and m/2-M1/, and an additional pair m/1-P4/ which also fulfils the same function, considerably augmenting the length of the cutting blade. Study of several mandibles of Prionogale and the maxilla and mandible of Namasector via tomographic CT-Scan indicates that there are no dental germs corresponding to permanent premolars. The suppression of premolars and the highly derived morphology of the molar dentition of the two species of Prionogalidae render it difficult to determine the systematic position of this clade of hypercarnivores, which comprise part of the radiation of Hyainailouroidea of the Miocene of Africa. Keywords: Miocene, Africa, Hyaenodonta, Prionogalidae, Systematics, CT-scan tomography.