Lewis Niles Black (born August 30, 1948) is an American stand-up comedian and actor. His comedy routines often escalate into angry rants about history, politics, religion, and cultural trends.

He hosted the Comedy Central series Lewis Black's Root of All Evil and makes regular appearances on The Daily Show delivering his "Back in Black" commentary segment, which he has been doing since The Daily Show was hosted by Craig Kilborn. He was voted 51st of the 100 greatest stand-up comedians of all time by Comedy Central in 2004; and was voted 5th in Comedy Central's Stand Up Showdown in 2008 and 11th in 2010. In 2015, he appeared as the voice of Anger in the Pixar film Inside Out, a role he reprises in the 2024 sequel.

Lewis Black is also a spokesman for the Aruba Tourism Authority, appearing in television ads that first aired in late 2009 and 2010. He has served as an "ambassador for voting rights" for the American Civil Liberties Union since 2013. Since 2022, he has been the chair of the executive committee and the board of directors of the Kurt Vonnegut Museum and Library. He had been an honorary member of the board for about 10 years before that.

When not on the road performing, Black resides in Manhattan, but also maintains a residence in Chapel Hill, North Carolina.