Ptolemy XI Alexander II[note 1] (Greek: Πτολεμαῖος Ἀλέξανδρος, Ptolemaĩos Aléxandros) was a member of the Ptolemaic dynasty who ruled Egypt for a few days in 80 BC.

Rome's Sulla wanted a pro-Roman ruler on the throne, and sent the young son of Ptolemy X to Egypt, displaying Ptolemy Alexander's will in Rome as supposed justification for this obvious interference.

The will also apparently required Ptolemy XI to marry Berenice III, who was his stepmother, cousin, and possible half-sister.

Nineteen days after the marriage, Ptolemy murdered his bride for unknown reasons, an unwise move since Berenice was very popular.

Peter Green, Alexander to Actium (University of California Press, 1990), pp.