Adad-nirari III (also Adad-narari) is King of Assyria from 811 to 783 BCE.

He was the son and successor of Shamshi-Adad V, and was apparently quite young at the time of his accession, because for the first five years of his reign his mother Shammuramat acted as regent, which may have given rise to the legend of Semiramis.

It is widely rejected that his mother acted as regent, but she was surprisingly influential for the time period.