Gorbonianus (Welsh: Gwrviniaw) was a legendary king of the Britons as accounted by Geoffrey of Monmouth. He was the eldest son of King Morvidus.

Gorbonianus was unlike many kings in that he loved equity and ruled frugally. He often would pay his respects to the gods and ruled his people with common justice and laws. Many temples were built or restored in his reign and the kingdom grew increasingly more wealthy. Protection was given to the country farmers from their masters. He gave wealth to his soldiers as to stop unnecessary violence against the peasantry or neighbours.

He reigned for some time then died and was buried in Trinovantum. He was succeeded by his brother, Archgallo.