Antiochus VI Dionysus (c. 148–138 BC) was king of Syria. He was the son of Alexander Balas and Cleopatra Thea, daughter of Ptolemy VI of Egypt.

Antiochus VI did not actually reign. He was nominated in 144 BC by the general Diodotus Tryphon as heir to the throne in opposition to Demetrius II. In 142 BC,Diodotus deposed and succeeded him and in 138 BC killed him.