As a child at the age of seven, Neuwirth began lessons on trumpet. She later studied composition in Vienna at the Vienna Academy of Music and Performing Arts under Erich Urbanner, while studying at the Electroacoustic Institute. Her thesis was written on the music in Alain Resnais's film L'Amour à mort. In 1985/86, she studied music and art at the San Francisco Conservatory of Music with Elinor Armer. In 1993/94 she studied with Tristan Murail and worked at IRCAM, producing such works as "...?risonanze!..." for viola d'amore. Earlier in her career, Neuwirth had the chance to meet with Italian composer Luigi Nono, who had similarly radical politics, and has claimed this had a strong influence on her life. In 2000, Neuwirth was appointed Composer-in-Residence of the Royal Philharmonic Orchestra of Flanders, Antwerp, and in 2002 she was appointed Composer-in-Residence at the Lucerne Festival (together with Pierre Boulez).
She has numerous chamber music works released on the Kairos label, and has collaborated with Elfriede Jelinek on an opera of David Lynch's film Lost Highway incorporating both live and pre-recorded audio and visual feeds, alongside other electronics. The world premiere took place in Graz in 2003, performed by the Klangforum Wien with the electronics realized at the Institut für Elektronische Musik (IEM). The American premiere of the opera took place at Oberlin College in Oberlin, Ohio, and featured further performances at Columbia University's Miller Theatre in New York City, produced by Oberlin Conservatory and The Oberlin Contemporary Music Ensemble. The surround recording released at Kairos was awarded the Diapason d'Or. The UK premiere took place at the Young Vic in London in April 2008, in a co-production with the English National Opera, directed by Diane Paulus and conducted by Baldur Brönnimann.
In 2008 she was awarded the Heidelberger Künstlerinnenpreis (Heidelberg Prize for Female Artists).
- Kloing! and A songplay in 9 fits Hommage à Klaus Nomi (2011) A music-theatre evening compiled by Olga Neuwirth
- THE OUTCAST – Homage to Herman Melville (2009-2011) A musicstallation theatre with video. Libretto by Barry Gifford and Olga Neuwirth with monologues for Old Melville by Anna Mitgutsch
- American Lulu (2006-2011) New interpretation of Alban Berg’s opera Lulu by Olga Neuwirth
- Bählamms Fest (1997/98) Music theatre in thirteen pictures. Text: Elfriede Jelinek after Leonora Carrington
- Masaot/Cloacks without Hands (2013) for Orchester
- anaptyxis (2000) for Orchester
- Clinamen / Nodus (1999) for Orchester
- Photophorus (1997) for two e-guitars and orchestra
- Sans soleil (1994) Distorting mirror for two ondes martenot, orchestra and live electronic and 2 Ondes Martenot
- Ishmaela's White World (2012)
- Hommage à Klaus Nomi (2009) Chamber orchestra version
- Construction in space (2000) for 4 soloists, 4 ensemble groups and live-electronic
- The Long Rain A video opera with surround-screens (1999/2000) for 4 soloists, 4 ensemble groups, live-electronic, after a story by Ray Bradbury
- Elfi und Andi (1997) for speaker, e-guitar, double bass, bass clarinet, saxophone and two playback-CD’s (voice from tape: Marianne Hoppe). Text: Elfriede Jelinek
- voluta / sospeso (1999) for basset horn, clarinet, violin, violoncello, percussion and piano
- ...ad auras... in memoriam H. (1999)
- settori (1999) for string quartet
- Ondate II (1998) for saxophone quartet
- Akroate Hadal (1995) for string quartet