Dionysius Soter (Ancient Greek: Διονύσιος Σωτήρ, romanized: Dionysios Sōtēr; epithet means "the Saviour") was an Indo-Greek king in the area of eastern Punjab.

[1] According to Osmund Bopearachchi, he reigned c. 65–55 BCE and inherited the eastern parts of the kingdom of the important late ruler Apollodotus II.

Dionysios was probably pressured by the invasions of the Indo-Scythians, and also had to deal with Hippostratus, a more important king who had inherited the western part of the kingdom of Apollodotus II.

Dionysius was the first in the line of late kings who issued only silver drachms, but no tetradrachms, which was likely due to his limited resources.

According to Bopearachchi, Dionysius inherited only the inferior celators of Apollodotus II, which he associates with mints in eastern Punjab.