Under a Blood Red Sky is a live album by Irish rock band U2, produced by Jimmy Iovine and released on 21 November 1983. Along with its companion concert film, U2 Live at Red Rocks: Under a Blood Red Sky, the release helped establish U2's reputation globally as a live act.
The album consists of live recordings from three shows on the band's War Tour, from Colorado and Boston in the US and from Germany.
An accompanying concert video entitled U2 Live at Red Rocks: Under a Blood Red Sky was released the following year. The film was recorded entirely at the outdoor Red Rocks Amphitheatre on 5 June 1983, while two songs from that show are included on the album.
The title is taken from the lyrics of the song "New Year's Day", originally released on U2's War album.