The Roman theatre of Dion is located near the Hellenistic theatre, to the south-east of the latter, outside the city limits. Dating from the second century BC, it probably replaced its predecessor, which seemed to degrade after 168 BC.

Smaller than the Hellenistic theatre, it was built on flat land with a view towards the east. Its form reminds the theatres of Korinthos and Patras: a cavea of 16.45m in diameter, an orchestra of 10.70m in diameter, the scene and the proscenium. The cavea, surrounded by a high stone-built semicircular wall, was divided into four sections by three narrow staircases. The tiers lied on the roofs of eleven radiating vaulted cuneiform spaces, overlooking the semicircular internal corridor lining the outer wall, at the exception of the extremes that communicated with the parodoi (passageways, public entrances). Only a few of the estimated 24 benches are currently preserved. The scenic building was independent from the cavea and richly adorned with precious marble revetment and sculptures; unfortunately, its larger part has been destroyed by artesian flows. At the evidence of coins found during the excavation, at least four spots of the cavea and the scene were modified during the last quarter of the fourth century AD, perhaps due to partial precipitation of the theatre because of earthquakes or partial change of use.