Ptolemy of Mauretania was the last Roman client king and ruler of Mauretania for Rome. He was the son of Juba II, the king of Numidia and a member of the Berber Massyles tribe, as well as a descendant of the Ptolemaic dynasty via his mother Cleopatra Selene II.

Mauretania is the Latin name for a region in the ancient Maghreb. It extended from central present-day Algeria to the Atlantic, encompassing northern present-day Morocco, and from the Mediterranean in the north to the Atlas Mountains. Its native inhabitants, of Berber ancestry, were known to the Romans as the Mauri and the Masaesyli.