The ISS Thermopylae was a warship of the Imperial Starfleet of the Terran Empire.

In the late 2240s, the Thermopylae and the ISS Indomitable were dispatched to investigate Klingon weapon tests at Donatu V. The Terran ships were detected and the Thermopylae was subsequently destroyed in the battle. (Mirror Universe short story: "Ill Winds")