The Ren & Stimpy Show, commonly referred to as simply Ren & Stimpy, is an American animated comedy television series created by John Kricfalusi for Nickelodeon. The series follows the misadventures of Ren Höek, an emotionally unstable and psychotic chihuahua dog; and Stimpy, a good-natured and dimwitted Manx cat. Originally produced by Spümcø, the series aired on Nickelodeon from August 11, 1991, to December 16, 1995, with its last episode airing on MTV on October 20, 1996, spanning a total of five seasons and 52 episodes. The third to be aired of the original three Nickelodeon animated series known as "Nicktoons", alongside Doug and Rugrats, it is one of the progenitor series of the brand.

The series received widespread critical acclaim for its visuals, animation, and surreal nature. However, it generated significant controversy for its dark humor, adult humor, violence, and shock value, contributing to Kricfalusi's termination in 1992, due to altercations with Nickelodeon's Standards and Practices and production delays. Games Animation produced the remaining three seasons of the series, when it received criticism for a perceived decline in quality.

An adult animated reboot, Ren & Stimpy "Adult Party Cartoon", was produced by Kricfalusi and Spümcø and aired on Spike TV in 2003, being canceled early due to production delays and negative critical reception from both critics and fans of the original series. On August 5, 2020, Comedy Central announced a second reboot of the series without Kricfalusi's involvement.