The Gorn King was the title given to the leader of the Gorn Hegemony.

In an alternate universe's 2384, Xrathis held the position of King of the Gorn and after a vessel of the Hegemony attacked a Klingon ship, he claimed that the Gorn crew were rogues. Despite this being the case, he refused to hand back any Klingon Defense Force survivors back to the Klingon Empire. This decision led to Chancellor Martok expelling the Gorn diplomats from the Klingon Empire. (ST website: The Path to 2409)

Other sources indicate that the leaders title of the Gorn was given the name of Imperator of the Gorn Hegemony.