This article lists compositions written for the viola. The list includes works in which the viola is a featured instrument: viola solo, viola and piano, viola and orchestra, ensemble of violas, etc. Catalogue number, date of composition and publisher (for copyrighted works) are also included. Ordering is by composer surname.

This pages lists composers whose surname falls into the O to R alphabetic range. For others, see respective pages: List of compositions for viola: A to B List of compositions for viola: C to E List of compositions for viola: F to H List of compositions for viola: I to K List of compositions for viola: L to N List of compositions for viola: S List of compositions for viola: T to Z

O Charles Oberthür (1819–1895)Zeyringer, Franz. Literatur für Viola. New Edition. Hartberg: Schönwetter, 1985. Le pauvre Savoyarde (The Poor Savoyard) or Le pauvre petite Savoyarde, Romance for viola and harp (or piano), Op. 119 (1855) Jana Obrovská (1930–1987) Concertino for violin, viola, double bass and string orchestra (1981); Český Hudební Fond Smutek sluší viole (Sadness Suits the Viola), Fantasie for viola and chamber orchestra (1978); Český Hudební Fond Irina Odăgescu-Țuțuianu (b. 1937) Melos, Sonata for viola solo, Op. 48 (1982); Editura Muzicală Helmut Oehring (b. 1961) Plath, S. for 2 violas (or other instruments) (1998) Sexton A. for viola solo (1996); Bote & Bock; Boosey & Hawkes Michael Oesterle (b. 1968) Big City, little city for solo viola and chamber ensemble (2007) Chaucer Canticles for 2 sopranos, 2 percussionists and viola (2003) Will Ogdon (1921–2013) Variation Suite for violin and viola (1995–1996); Association for the Promotion of New Music Eduard Oja (1905–1950) Melanhoolsed öökullid (Melancholic Owls) for viola and piano (1937) Eoin O'Keeffe (b. 1979) Trio and Over Again for flute, viola and harp (2005); Contemporary Music Centre Ireland Mehmet Okonşar (b. 1961) Ahmet Taner Kışlalı Anısına (Ahmet Taner Kışlalı In Memoriam) for viola solo (2004) Kaleidoscope No. 3 for viola and piano (2006) Kjartan Ólafsson (b. 1958) Concerto for viola and orchestra (1995); Íslenzk Tónverkamiðstöð Dimma (Dusk) for viola and piano (1985); Íslenzk Tónverkamiðstöð Jane O'Leary (b. 1946) Why the Hill Sings for viola and piano (2004); Contemporary Music Centre Ireland Vivienne Olive (b. 1950) And the Willows Drowse and Sleep for flute, viola and harp (2002); Furore Verlag At All, at All ... for 3 mezzo-sopranos and 3 violas (1971); Furore Verlag Pantjelang Lullaby for viola and cello (1995); Furore Verlag Rondel for viola and piano (1979); Tonos International Music Editions John Oliver (b. 1959) A Dream of Africa for viola and guitar (2006, 2007) New Bloom for flute, violin and viola (1988) 3 Trains for viola and piano (2000); Canadian Music Centre Sonare 1 for viola solo (1982, revised 1992); Canadian Music Centre Juan Oliver y Astorga (1733–1830) Sonata No. 1 in C minor for viola and basso continuo (1803); Cornetto-Verlag Sonata No. 2 in G major for viola and basso continuo (1804); Cornetto-Verlag Sonata No. 3 in F minor for viola and basso continuo (1804); Cornetto-Verlag Sonata No. 4 in C major for viola and basso continuo (1805); Cornetto-Verlag Sonata No. 5 in C minor for viola and basso continuo (1807) Betty Olivero (b. 1954) Neharót Neharót (נהרות, נהרות) for solo viola, accordion, percussion, 2 string orchestras and tape (2006–2007); Israel Music Institute Per Viola (לויולה) for viola solo (1993); Israel Music Institute Sparre Olsen (1903–1984) Norsk kjærleikssong (Norwegian Love Song) for viola or cello and piano, Op. 36 No. 3 (1946); Norsk Musikforlag Tre Dialoger (Three Dialogues) for flute and viola, Op. 50 (1976); Musikk-Huset Forlag George Onslow (1784–1853) Sonata in F major for viola and piano, Op. 16 No. 1 (1819); original for cello and piano Sonata in C minor for viola and piano, Op. 16 No. 2 (1819); original for cello and piano Sonata in A major for viola and piano, Op. 16 No. 3 (1819); original for cello and piano György Orbán (b. 1947) Sonata for viola and piano (1997) Ben-Zion Orgad (1926–2006) Monologue (מונולוג) for viola solo (1957); Israeli Music Publications Leo Ornstein (1893–2002) Ballade for saxophone (or clarinet, or viola) and piano, S609 (1955); Poon Hill Press Two Fantasies for viola and piano, S606-607 (1970s); Poon Hill Press Buxton Orr (1924–1997) Episodes for English horn or viola and piano (1966); Gamber Press; British Music Information Centre Kate's Piece for alto flute and viola (1997); Gamber Press Refrains I for English horn or viola and piano (1970); Gamber Press; British Music Information Centre Refrains II for clarinet, viola and piano (1971); Gamber Press; British Music Information Centre Robin Orr (1909–2006) Sicilienne and Chaconne for viola and piano (1949); Hinrichsen Edition Sonata for viola and piano (1947); Oxford University Press Juan Orrego-Salas (1919–2019) A Greeting Cadenza for William Primrose for solo viola, Op. 65 (1970); Frangipani Press; MMB Music Mobili for viola and piano, Op. 63 (1967); Peer Music Classical Sonata a dúo for violin and viola, Op. 11 (1945); MMB Music Jackie Orszaczky (1948–2008) Ghost for viola and cello (2005) Léon Orthel (1905–1985) Sonata for viola and piano, Op. 52 (1964–1965); Donemus Nigel Osborne (b. 1948) Concerto for viola and orchestra (2008); University of York Music Press Transformations 1 "Feminist Theologies" for 2 violas (2007); University of York Music Press Michiru Ōshima (b. 1961) Concerto Voix de la vie (ヴィオラ協奏曲「命の声」) for viola and orchestra (2009–2010) Sonata (ビオラ・ソナタ) for viola and piano (2013) In the Kitchen for viola solo (2015); composed for Sylvain Durantel and La Cuisine à l'alto Reine Colaço Osorio-Swaab (1881–1971) Sonata No. 3 for viola and piano (1952); Donemus Suite (Trio No. 1) for flute, violin and viola (1940); Donemus Trio No. 3 for 2 violins and viola (1950); Donemus Tsaddiék, Intermezzo for viola and piano (1953); Donemus Slavko Osterc (1895–1941) Sonata for viola and piano Willy Ostijn (1913–1993) Capriccio for violin (or flute, or clarinet), viola and piano (1965); CeBeDeM Elegie for viola and piano (1956); CeBeDeM Fata Morgana for clarinet, viola and piano (1952) Romanza for viola and piano; CeBeDeM Serenata for violin (or viola) and string orchestra (1954); CeBeDeM Trio in B minor for violin (or flute), viola and piano (1960); CeBeDeM Trio "Twilight" for clarinet, viola and piano (1952) Otakar Ostrčil (1879–1935) Sonatina for viola, violin and piano, Op. 22 (1925); Universal Edition David Ott (b. 1947) Concerto for viola and orchestra (1989); Lauren Keiser Music Publishing Hall Overton (1920–1972) Sonata for viola and piano (1959); American Composers Alliance

P Luis de Pablo (1930–2021) Anatomías for viola solo, 2 clarinets, horn, trombone and harp (2005–2007); Edizioni Suvini Zerboni Ex voto for violin and viola (1995); Edizioni Suvini Zerboni Monólogo for viola solo (1990–1992); Edizioni Suvini Zerboni Giorgio Pacchioni (b. 1947) Baroquefantasy No. 2 for viola and piano (1996); Ut Orpheus Edizioni Niccolò Paganini (1782–1840) Caprice No. 24; arranged for viola and piano by William Primrose; Carl Fischer La Campanella; arranged for viola and piano by William Primrose; Edition Schott Sonata per la Gran' Viola in C minor for viola and orchestra (1834) Christopher Painter (b. 1962) Sonata for viola solo, Op. 60 (2011); Oriana Publications Sonata for viola and piano, Op. 18 (1986); Vanderbeek & Imrie Émile Paladilhe (1844–1926) Danse noble (Concertino de violes) for 2 violas (or violin and viola) and cello (1902) Johannes Palaschko (1877–1932) Alte Meister für junge Spieler: leichte klassische Stücke (Old Masters for Young Players: Easy Classical Pieces); arrangements for viola and piano (published 1930); Edition Schott 20 Etüden für Viola zur Förderung der Technik und des Vortrags (20 Viola Studies for Technical Advancement and Performance) for viola solo, Op. 36 (1904 or 1905); F. Kistner & C.F. Siegel; International Music Company 10 Künstler-Etüden (10 Artist Studies) for viola solo, Op. 44 (1907); Wilhelm Zimmerman 10 Viola-Studien für vorgerückte Spieler (10 Viola Studies for Advanced Players) for viola solo, Op. 49 (1910); C.F. Schmidt; International Music Company 12 Etüden (12 Studies) for viola solo, Op. 55 (1912); Steingräber; International Music Company 12 Studi (12 Studies) for viola solo, Op. 62 (1923); G. Ricordi 15 Studien (15 Studies) for viola solo, Op. 66 (1926); Edition Schott 15 Studi (15 Studies) for viola solo, Op. 70 (1926); G. Ricordi 24 Études Mélodiques (24 Melodious Studies) for viola (viola alta) solo, Op. 77 (1927); Alphonse Leduc 24 leichte melodische Viola-Studien (24 Easy and Melodious Studies for the Viola) for viola solo, Op. 86 (1930); Edition Schott 25 Studi facili e melodici (25 Easy and Melodious Studies for the Viola) for viola solo in 1st and 3rd positions, Op. 87 (1928); G. Ricordi Melodische Etüden (Melodious Studies), 25 Etudes for viola solo, or with optional piano accompaniment, Op. 92 (1929); Simrock 25 melodische Studien (25 Melodious Studies) for viola solo, Op. 96 (1930); C. Merseberger; Carl Fischer Roman Palester (1907–1989) Concerto for viola and orchestra (1975–1978); Polskie Wydawnictwo Muzyczne Trio for flute, viola and harp (1985) Robert Moffat Palmer (1915–2010) Sonata for viola and piano (1948); Peer Music Juan Pampin (b. 1967) Nada for viola and electronic sounds (2006) Roxanna Panufnik (b. 1968) Canto for viola solo (2018) Yiannis Papaioannou (1910–1989) Night (Νυχτερινό) for flute, viola and harp (1937) Pastorale (Παστοράλε) for flute, viola and harp (1938) Romanesca (Ρομανέσκα) for flute, viola and harp (1938) Satyricon (Σατυρικόν) for violin and viola (1978); Philippos Nakas Music House Trio for flute, viola, guitar (1967) Boris Papandopulo (1906–1991) Sonata for viola and piano (1963); Saveza kompozitora Jugoslavije Gérard Pape (b. 1955) For Maurizio for amplified viola (2003) Le Fleuve du désir VI (The River of Desire VI) for viola, tape and live electronics (1994); Éditions Musicales Européennes; United Music Publishers Jean Papineau-Couture (1916–2000) Prouesse for viola solo (1985, revised 1987); Canadian Music Centre Trio en quatre mouvements for clarinet, viola and piano (1974); Canadian Music Centre Désiré Pâque (1867–1939) Sonata for viola and piano, Op. 85 (1915) Suite de deux pièces (Romance et Allegro Scherzando) (Suite of 2 Pieces) for viola and piano, Op. 24 (1892); published as Op. 49 Suite No. 1 for violin, viola and piano, Op. 17 (1891) Suite No. 2 for violin, viola and piano, Op. 20 (1892) Suite No. 3 for violin, viola and piano, Op. 26 (1893) Suite No. 4 in B major for violin, viola and piano, Op. 27 (1893) Suite No. 5 for violin, viola and piano, Op. 34 (1896) Robert Parris (1924–1999) Concerto for viola and orchestra (1956); American Composers Alliance Sonata for viola and piano (1957); American Composers Alliance Ian Parrott (1916–2012) Aquarelle for clarinet or viola and piano (1952); Chester Music Duetto for violin and viola (1986) Boris Parsadanian (1925–1997) Sonata for viola solo (1977) Michael Parsons (b. 1938) Pentatonic for violin or viola solo (1975, revised 1984); British Music Information Centre Arvo Pärt (b. 1935) Es sang vor Iangen Jahren (Motette für de la Motte) for alto or countertenor, violin and viola (1984); Universal Edition Fratres for viola and piano (1977, 2003) or for viola and chamber orchestra (1997, 2008); Universal Edition Spiegel im Spiegel for viola and piano (1978); Universal Edition Tabula Rasa, Double Concerto for 2 violins (or violin, viola) and string orchestra with prepared piano (1977); Universal Edition Ödön Pártos (1907–1977) Agada (אגדה; Legend) for solo viola, percussion and piano (1960); Israel Music Institute