Events in the year 1820 in Art.

• April 8 - The Venus de Milo is discovered on the island of Melos (Greek: Milos).
• Publication of William Blake's prophetic book Jerusalem: The Emanation of the Giant Albion (colored engravings) is completed in London (commenced 1804).

• William Blake – The Ghost of a Flea
• Augustus Wall Callcott – A Dead Calm on the Medway
• Antonio Canova – George Washington (installed in the North Carolina State House in 1821 – destroyed by fire-induced structural collapse in 1831)^[1]
• John Constable – Harwich Lighthouse
• Johan Christian Dahl – View from a Window at Quisisana
• William Etty
  • Female Nude in a Landscape
• Francisco Goya – Self-portrait with Dr Arrieta
• Francesco Hayez - Pietro Rossi
• George Hayter
  • Portrait of Lord Holland
  • Venus supported by Iris, complaining to Mars
• Thomas Lawrence – Portrait of Lord Liverpool
• Thomas Luny – Bombardment of Algiers
• Jean-Baptiste Regnault
  • The Judgement of Paris (approximate date)
  • Love and Hymen drinking from the cup of Friendship (Musée Bossuet, Meaux)

• Joseph Karl Stieler - Portrait of Beethoven
• John Trumbull – Surrender of Lord Cornwallis
• J. M. W. Turner – Rome from the Vatican
• David Wilkie – Reading the Will

• February 18 – Pierre Alexandre Schoenewerk, French sculptor (died 1885)
• February 28 – John Tenniel, English illustrator (died 1914)
• April 6 – Nadar, French photographer and caricaturist (died 1910)
• May 12 – Josef Mánes, Czech painter (died 1871)
• July 9 – John Wright Oakes, English landscape painter (died 1887)^[2]
• July 25 – Henry Doulton, English potter (died 1897)
• November 23 – Ludwig von Hagn, German painter (died 1898)^[3]
• December – Eugène Fromentin, French painter (died 1876)
• December 16 – George Scharf, English art critic and curator (died 1895)
• date unknown – John Frederick Herring, Jr., English sporting and equestrian painter (died 1897)

• January 29 – George III of the United Kingdom, patron of the arts and collector (born 1738)
• March 8 – Kitao Shigemasa, Japanese ukiyo-e artist from Edo (born 1739)
• March 9 – Hermanus Numan, Dutch artist, art theorist, and publisher (born 1744)
• March 11 – Benjamin West, American-born English painter (born 1738)^[4]
• March 27 – Gerhard von Kügelgen, German painter of portraits and history paintings (born 1772)^[5]
• May 17 – Vincenzo Brenna, Italian painter and house architect of Paul I of Russia (born 1747)
• May 26 – Antonio Longo, Italian priest and painter (born 1742)^[6]
• September 15 – Okada Beisanjin, Japanese painter (born 1744)
• October 10 – Uragami Gyokudō, Japanese musician, painter, poet and calligrapher (born 1745)
• date unknown
  • Pietro Bonato, Italian painter and engraver (born 1765)
  • Jean Simeon Rousseau de la Rottiere, French decorative painter (born 1747)
  • Quirinus van Amelsfoort, Dutch allegorical, historical and portrait painter (born 1760)