The Basilica Julia (Italian: Basilica Giulia), is a structure that once stood in the Roman Forum. It was a large, ornate, public building used for meetings and other official business during the early Roman Empire. Its ruins have been excavated. What is left from its classical period are mostly foundations, floors, a small back corner wall with a few arches that are part of both the original building and later Imperial reconstructions and a single column from its first building phase.

The Basilica Julia was built the site of the earlier Basilica Sempronia (170 BC) along the south side of the Forum, opposite the Basilica Aemilia. It was initially dedicated in 46 BC by Julius Caesar, with building costs paid from the spoils of the Gallic War, and was completed by Augustus, who named the building after his adoptive father.

The building burned shortly after its completion, but was repaired and rededicated in AD 12. The Basilica was again reconstructed by the Emperor Diocletian after the fire of AD 283.

The Basilica housed the civil law courts and tabernae (shops), and provided space for government offices and banking. In the first century, it also was used for sessions of the Centumviri (Court of the Hundred), who presided over matters of inheritance. In his Epistles, Pliny the Younger describes the scene as he pleaded for a woman whose 80-year-old husband had disinherited her within days of taking a new wife.