O

Alejandro Obregón (1920–1992), Colombian painter, muralist, sculptor and engraver

Bencho Obreshkov (1899–1970), Bulgarian painter

Jacques-François Ochard (1800–1870), French artist and teacher

Jacob Ochtervelt (1634–1682)

Leonard Ochtman (1854–1935), American Impressionist painter

Ogata Gekkō (1859–1920)

Ogata Kenzan (1663–1743)

Ogata Kōrin (1658–1716)

Juan O'Gorman (1905–1982), Mexican painter and architect

Ogura Yuki (1895–2000)

Dorothea Warren O'Hara (1873–1972), American ceramic artist

Ohara Koson (1877–1945)

Doug Ohlson (1936–2010)

Michalis Oikonomou (1888–1933)

Okada Beisanjin (1744–1820)

Okada Hanko (1782–1846)

Okamoto Tarō (1911–1996)

Georgia O'Keeffe (1887–1986), American artist

Aloysius O'Kelly (1853–1941)

Okuda Gensō (1912–2003)

Okumura Masanobu (1686–1764)

Okumura Togyu (1889–1990)

Jules Olitski (1922–2007), American abstract painter, printmaker, and sculptor

Viktor Oliva (1861–1928), Czech painter and illustrator

Nathan Oliveira (1928–2010), American painter, printmaker, and sculptor

Olivia Peguero (born 1963), Dominican American painter and sculptor

Ceferí Olivé (1907–1995), Catalan watercolor painter

Madge Oliver (1875–1924), British painter

Francisco Oller (1833–1917)

Frank O'Meara (1853–1888)

Onchi Koshiro (1891–1955)

Julian Onderdonk (1882–1922)

Ono Tadashige (1909–1990)

Maria van Oosterwijk (1630–1693), Dutch Baroque painter, specializing in still-lifes

Bruce Onobrakpeya (born 1932), printmaker, painter and sculptor

John Opie (1761–1807), Cornish historical and portrait painter

Andrea Orcagna (1320–1368), Italian painter, sculptor, and architect

William Quiller Orchardson (1835–1910), Scottish portraitist and painter of domestic and historical subjects

Edward Otho Cresap Ord, II (1858–1923), American painter & poet

Bryan Organ (born 1935), English painter

Emil Orlik (1870–1932), Austrian painter, etcher, and lithographer

Aleksander Orłowski (1777–1832), Polish painter, sketch maker, and pioneer of lithography

José Clemente Orozco (1883–1949), Mexican social realist painter

Sir William Orpen (1878–1931), Irish portrait painter

Manuel Ortiz de Zarate (1887–1946), Chilean painter

George Earl Ortman (1926–2015)

Erik Ortvad (1917–2008), Danish painter, founding member of the COBRA avant-garde movement

Walter Osborne (1859–1903)

Adriaen van Ostade (1610–1685), Dutch genre painter

Isaac van Ostade (1621–1649)

Ilya Ostroukhov (1858–1929)

Ota Masamitsu (1892–1975)

Otake Chikuha (1878-1936)

Johann Friedrich Overbeck (1789–1869), German painter and member of the Nazarene movement

Auseklis Ozols (born 1941), American painter and teacher