Prionurus biafraensis, the Biafra doctorfish, is a species of marine ray-finned fish belonging to the family Acanthuridae, the surgeonfishes, unicornfishes and tangs.

[5] Prionurus biafrensis has a deep, oblong and compressed body with its deepest part fitting into its standard length 1.8 times.

The snout is distinct as there is a clear indent of the dorsal profile between the maxilla and the upper edge of the orbit.

[2] Prionurus biafraensis is found in the Gulf of Guinea around the island of Sao Tomé and along the African coast from Cap Lopez in Gabon to Pointe Noire in the Republic of Congo.

[2] It occurs at depths between 5 and 25 m (16 and 82 ft) close to rocky shorelines where it is typically encountered in small groups.