Keith Mann is a British animal rights campaigner and writer, alleged by police in 2005 to be at the top of the Animal Liberation Front (ALF) pyramid. He is the author of From Dusk 'til Dawn: An Insider's View of the Growth of the Animal Liberation Movement (2007). Viewed as a cause célèbre within the global animal rights movement, he has acted as a spokesman for the ALF, attracting the support of celebrities such as Carla Lane and Celia Hammond. He was the subject in 2006 of a Channel 4 documentary by Yousaf Ali Khan, Angels of Mercy?.

Mann first came to widespread public attention after being sentenced in 1994 to 14 years imprisonment, reduced to 11 years on appeal—one of the longest sentences handed down to an animal rights activist—after being arrested in 1991 for conspiracy to set meat lorries on fire and for having escaped from custody; he was found by police working in an animal sanctuary run by the Celia Hammond Animal Trust, which had employed him unaware of who he was.

He told The Guardian in 2005 that the government in the UK had undermined the right to protest, which had driven activists to engage in tactics such as economic sabotage. He has since turn his attention to mainstream politics, and stood unsuccessfully for parliament in the Oxford West and Abingdon constituency for the Animal Protection Party in the May 2010 general election. He said the point of fielding animal rights candidates was not so much to gain power, but to have a voice in the election process.