Ptolemy X Alexander (ca. 140–88 bc). Younger son of Ptolemy VIII Physcon and Cleopatra III and brother of Ptolemy IX Soter II; ruler of the Ptolemaic empire in Egypt from 107 to 88 bc.

When Ptolemy VIII died, Cleopatra III wanted to make their Alexander king. However, the people of Alexandria, Egypt, demanded that the older son, Soter II, take the throne. Alexander ruled as governor and king of Cyprus instead, but twice during his brother’s reign their mother temporarily put Alexander on the throne in Egypt.

When Soter II was permanently deposed in 107 bc, Alexander became coregent with his mother. After her death (or murder) in 101 bc, Alexander married Cleopatra Berenice, his brother’s daughter. In 88 bc, the Alexandrians expelled him from Egypt, and he was later killed in battle while trying to retake his position as Egyptian monarch. Soter II then reclaimed the throne.