Galileo Galilei is an opera based on excerpts from the life of Galileo Galilei which premiered in 2002 at Chicago's Goodman Theatre, as well as subsequent presentations at the Brooklyn Academy of Music's New Wave Music Festival and London's Barbican Theatre. Music by Philip Glass, libretto and original direction by Mary Zimmerman and Arnold Weinstein. The piece is presented in one act consisting of ten scenes without break.

Galileo Galilei is Glass' 18th opera, and draws from letters of Galileo and his family, and various other documents, to retrospectively journey through Galileo's life. Opening with him as an old, blind man after the trial and Inquisition for his heresy, it explores his religiosity as well as his break with the church, and expands into the greater, oscillating relationship of science to both religion and art. It reaches its end with Galileo — as a young boy — watching an opera composed by his father, Vincenzo Galilei, who was a member of the Florentine Camerata, an association of artists who are credited with creating the art form that came to be known as opera. Ironically, his father's opera is about the motions of the celestial bodies.

Recently, the opera has been revived with new productions in 2012 by Madison Opera and Portland Opera. The Portland Opera production is being recorded by Orange Mountain Music and will be released in late 2012 as the first commercial recording of this work.