Oisc (alternately Oeric or Aesc) was an early King of Kent who ruled from about 488 to about 516.

Little is known about him, and the information that does survive regarding his life is often vague and suspect. He seems to have been the son or the grandson of Hengest, who led the initial Jutish conquest and settlement of Kent. Oisc was evidently regarded by later generations as having been the founder of the kingdom or of the royal line, since his descendants called themselves "Oiscingas" after him.

He was said to have been a leader of the Anglo-Saxons at the Battle of Mons Badonicus, in which they were defeated by the native Britons. In fact, he was the only one of their kings whose participation in this battle was recorded.