MU330 is an American ska punk band from St. Louis, Missouri. Formed by students of St. Louis University High School in 1988, MU330 played a self-described brand of music called "psycho ska", high energy ska punk marked by manic performances and humorous, often strange lyricism.

Since 1997, the band's musical direction has changed towards a more melodic and lyric-driven ska/indie rock sound, a combination that has been described as "Weezer meets The Specials".

Dan Potthast (guitar/vocals), Ted Moll (drums), Chris Diebold (bass guitar), and Robert Bell (trombone) have remained with MU330 since the band's inception, and the trombonist Gerry Lundquist has been a member for over two decades. There have been several different frontmen in the past, but Potthast has always been the band's principal songwriter and lyricist.