Mongrels, formerly known under the working titles of We Are Mongrels and The Un-Natural World, is a British puppet-based situation comedy series first broadcast on BBC Three between 22 June and 10 August 2010, with a making-of documentary entitled "Mongrels Uncovered" broadcast on 11 August 2010. A second series of Mongrels began airing on 7 November 2011.

The series revolves around the lives of five anthropomorphic animals who hang around the back of a pub in Millwall, the Isle of Dogs, London. The characters are Nelson, a metrosexual fox; Destiny, an Afghan hound; Marion, a "borderline-retarded" cat; Kali, a grudge-bearing pigeon; and Vince, Nelson's friend, a sociopathic foul-mouthed fox.

The show is aimed at an adult audience, features "neutering, incontinence, cannibalism and catnip overdoses" and humour styles such as slapstick and farce. For example, the first episode begins with a scene in which Marion, portrayed as desperately trying to revive his deceased owner, learns she has actually been dead for four months, whereupon he casually gives his cat friends permission to eat her. Mongrels has attracted accusations of plagiarism, with claims that Mongrels stole ideas from a similar Channel 4 show called Pets.