In the fictional Star Wars trilogy, the Rancor is described as a huge monsterous carnivore, at a height of 10 meters tall and are most likely found on the planet Dathomir. In Star Wars Episode VI: Return of the Jedi, the infamous criminal Jabba the Hutt, has a "pet" rancor below his palace to be used to get rid of unwanted or displeasing guests. Victims such as Jabba's slave girl Oola were dropped through a trap door into the death pit below and were eaten by the rancor for the amusement of his guest.

Luke Skywalker was also dropped in the pit and faced the rancor, without his lightsaber. When all looked hopeless, Luke managed to kill the giant beast.

The banished Jedi Knight Allya found herself on the planet of Dathomir, with other exiles, exiled for many different reasons. She taught them to tame the fierce rancors that ran wild through the thick evergreen forests of Dathomir. The tamed rancors then carried the witches from clan to clan.

Jedi Knight Tenel Ka used a rancor tooth to build both her first and second lightsaber.