Petrocephalus longicapitis is a species of electric fish in the family Mormyridae. It is found in the upper and middle Zambezi River, and in the Okavango in Angola.
This species reaches a length of .
The fish's name means longus (L.), "long"; capitis (L.), "of the head", referring to its long head length (25.8â 29.6% of SL).