Péter Eötvös (Hungarian: Eötvös Péter, pronounced [ˈøtvøʃ ˈpeːtɛr]; 2 January 1944 – 24 March 2024) was a Hungarian composer, conductor and academic teacher.

After studies of composition in Budapest and Cologne, Eötvös composed film music in Hungary from 1962. He played with the Stockhausen Ensemble between 1968 and 1976. He was a founding member of the Oeldorf Group in 1973, continuing his association until the late 1970s. From 1979 to 1991, he was musical director and conductor of the Ensemble InterContemporain, and from 1985 to 1988 he was principal guest conductor of the BBC Symphony Orchestra, after which he conducted several other orchestras.

As a composer, Eötvös was known for the operas Love and Other Demons and Three Sisters, both of which were performed outside Hungary. He was open to influences from different cultures.