Alexander Helios (late 40 BCE – unknown, but possibly between 29 and 25 BCE) is a Ptolemaic prince and is the eldest son of the Macedonian queen Cleopatra VII of Ptolemaic Egypt by Roman triumvir Mark Antony.

Alexander's fraternal twin sister is Cleopatra Selene II.

The twins are of Macedonian Greek and Roman heritage, Cleopatra names her son after her collateral ancestor, Alexander the Great.

His second name in Ancient Greek means "Sun"; this is the counterpart of his twin sister’s second name Selene, meaning "Moon".