Edgar Hovhannisyan, Hovhannisian or Oganesian (Armenian: Էդգար Հովհաննիսյան,Russian: Эдгар Сергеевич Оганесян; January 14, 1930, Yerevan – December 28, 1998, Yerevan) was an Armenian composer, Professor of Composition at the Yerevan State Conservatory, People's Artist of the USSR (1986).

He graduated from the Yerevan State Conservatory in 1953, then pursued post-graduate work at the Moscow Conservatory, where he worked under famed Armenian composer Aram Khachaturian. He was the director of the State Opera and Ballet Theater in Yerevan from 1962–1968, and Deputy Chairman of the Board of the Union of Composers of the Armenian SSR from 1956–1973. He was the rector of the Yerevan State Conservatory from 1986 to 1991.

Hovhannisyan is widely considered among the most influential Armenian composers of the 20th century. He is the author of ballets, including Joan of Arc, Sulamif (Shulamith) and Marmar. He experimented with various musical styles, including neo-classical, folk-based styles, and even jazz — such as in the Concert Variations for Saxophone and Jazz Orchestra — opera (Journey to Arzrum), various vocal-orchestral works (e.g. the oratorio Grigor Narekatsi, the hymn of Yerevan), and numerous film scores.