[1] As a child, he received a thorough musical education, which included becoming familiar with works by the Hungarian composer Béla Bartók.

[1] Eötvös's mother, a pianist, participated in the musical and intellectual life of Budapest and took her son to many performances and rehearsals of opera, operetta and theatre.

[4] During a period of ten years he developed personal musical preferences, for Gesualdo (the idea of the madrigal returns in pieces such as Drei Madrigalkomödien and Tri sestry), American jazz of the 1960s, electronic music (of which Karlheinz Stockhausen's figure was inseparable), and Pierre Boulez, among others.

[5] Eötvös received a German Academic Exchange Service (DAAD) scholarship to study abroad in 1966,[6][2] leaving for Cologne following the examples of Kurtág and Ligeti.

[7][8] This period also marks his first success as a composer with his instrumental piece Chinese Opera (1986),[3] written for the 10-year anniversary of the Ensemble InterContemporain.

[4] The piece constitutes a reflection on the theatricality of sound, as the composer spreads the musicians through the stage, a process also found in Three Sisters.

[10] Each movement is a tribute to directors he admired: Bob Wilson, Klaus Michael Grüber, Luc Bondy, Patrice Chéreau, Jacques Tati and Peter Brook.

Federico Capitoni cited an eclectic range of apparent elements and influences in Eötvös's music: the "lucid folly" of Edgar Varese and Frank Zappa, Ligeti's sense of irony, a certain "American" boldness, rigor reminiscent of dodecaphonists, and rhythms after his "beloved" Bartok and Stravinsky.

[4][17] Composing for film and theatre in his first large-scale compositions,[4] Eötvös learned the importance of timing and synchronisation.

[4] Sándor Weöres' poem Néma zene inspired two works for orchestra and voice, Atlantis (1995) and Ima (2002, also with chorus).

Reviewing a 2016 recording of Eötvös's concertante music with the composer himself conducting the Orchestre philharmonique de Radio France (Alpha 208), Capitoni noted Luciano Berio's and Frederic Rzewski's influence in the percussionist-vocalist of the 2012–2013 Speaking Drums (soloist Martin Grubinger).

His works were published by Durand,[18] Editio Musica Budapest,[19] Ricordi[20] and especially by Schott:[8] Eötvös was influenced by the music and theatre of Japan.

[22] The one-act opera Lady Sarashina was also based on Japanese tradition, the 11th-century diary of a lady-in-waiting;[1][6] it was premiered in Lyon on 8 April 2008.

His opera Love and Other Demons was based on Gabriel García Márquez' novella;[1] it was premiered on 10 August 2008 at Glyndebourne, UK.

[24] The one-act-opera Senza sangue (Without Blood) was composed to a libretto by Alessandro Baricco for two voices, as a work to be coupled with Bartók's Bluebeard's Castle.