Events from the year 1840 in art.
- March 4 – Alexander S. Wolcott and John Johnson open their "Daguerreian Parlor" on Broadway (Manhattan), the world's first commercial photography portrait studio.
- May 1 – Issue in the United Kingdom of the Penny Black, the world's first postage stamp, depicting the head of Queen Victoria engraved by Charles Heath and his son Frederick based on a sketch provided by Henry Corbould itself based on a cameo portrait by William Wyon, together with Mulready stationery. The stamp becomes valid for postage from May 6.
- September 30 – Foundation of Nelson's Column laid in London, Trafalgar Square being laid out and paved around it during the year.
- Jean-Antoine Alavoine and Joseph-Louis Duc – July Column, Place de la Bastille, Paris; incorporating Auguste Dumont's Génie de la Liberté and bas-reliefs by Antoine-Louis Barye and others
- Thomas Jones Barker – The Bride of Death
- François Bouchot – Napoleon Bonaparte in the coup d'état of 18 Brumaire in Saint-Cloud
- Théodore Chassériau
- Andromeda Chained to the Rock by the Nereids
- Diana Surprised by Actaeon
- Portrait of the Reverend Father Dominique Lacordaire, of the Order of the Predicant Friars
- Francis Danby – The Deluge
- Eugène Delacroix (Musée du Louvre, Paris)
- Entry of the Crusaders in Constantinople
- The Shipwreck of Don Juan
- William Etty – The Wrestlers (approximate date)
- Horatio Greenough – George Washington (statue, Washington, D.C.)
- Edwin Landseer – Laying Down The Law, or Trial by Jury (Chatsworth House, England)
- Robert Scott Lauder – David Roberts Esq. in the dress he wore in Palestine
- John Martin – The Eve of the Deluge (British Royal Collection) and The Assuaging of the Waters (Fine Arts Museums of San Francisco)
- John Christian Schetky – Loss of the Royal George
- Armand Toussaint – Persephone (sculpture) (approx. date)
- J. M. W. Turner – The Slave Ship, or Slavers throwing overboard the Dead and Dying — Typhoon coming on (Museum of Fine Arts, Boston)
- April 22 – Odilon Redon, French painter and graphic artist (died 1916)
- April 28 – Caroline Shawk Brooks, American sculptor (died 1913)
- May 2 – Philippe Solari, Provençal sculptor (died 1906)
- May 28 – Hans Makart, Austrian painter and designer (died 1884)
- July 8 – Heinrich von Angeli, Austrian society portrait painter (died 1925)
- August 14 – Briton Rivière, English painter (died 1920)
- September 27 – Thomas Nast, German American cartoonist (died 1902)
- November 12 – Auguste Rodin, French sculptor (died 1917)
- November 14 – Claude Monet, French Impressionist painter (died 1926)
- date unknown – Ida Göthilda Nilsson, Swedish sculptor (died 1920)
- probable – Timothy H. O'Sullivan, Irish American photographer of the American Civil War (died 1882)
- January 16 – František Tkadlík, Czech painter (born 1786)
- February 9 – Luke Clennell, English engraver and painter (born 1781)
- February 27 – Henry Wyatt, English portrait painter (born 1794)
- March 19 – Thomas Daniell, landscape painter (born 1749)
- March 30 – Beau Brummell, leader of fashion (born 1778)
- April 7 – William Heath, English satirical engraver (born 1794)
- April 10 – Alexander Nasmyth, painter (born 1758)
- May 5 – Robert Trewick Bone English painter of sacred, classical and genre scenes (born 1790)
- May 7 – Caspar David Friedrich, painter (born 1774)
- May 11 – Eduard Joseph d'Alton, German engraver and naturalist (born 1772)
- June 20 – Pierre-Joseph Redouté, flower painter (born 1759)
- July 6 – Johann Heinrich Ramberg, German painter and printmaker (born 1763)
- July 23 – Carl Blechen, German painter, specializing in fantastic landscapes with demons and grotesque figures (born 1798)
- August 30 - Jonas Damelis, Lithuanian neoclassicist painter (born 1780)
- October 28 – Reverend John Thomson, minister of Duddingston Kirk near Edinburgh, and landscape painter (born 1778)
- November 7 – Pierre Petitot, French sculptor (born 1760)
- December 11 – Franz Bauer, Austrian microscopist and botanical artist (born 1758)
- date unknown
- Hill, H. W. (1940). The Fight for the Penny Post. London: Warne. pp. 75–79.
- "Icons, a portrait of England 1840–1860". Archived from the original on August 17, 2007. Retrieved September 13, 2007.
- Blake, Richard. The Book of Postal Dates, 1635–1985. Caterham: Marden. p. 10.
- Penguin Pocket On This Day. Penguin Reference Library. 2006. ISBN 0-141-02715-0.
- Palmer, Alan; Veronica (1992). The Chronology of British History. London: Century Ltd. pp. 263–264. ISBN 0-7126-5616-2.
- Oxford University Press (June 21, 2012). Benezit Dictionary of British Graphic Artists and Illustrators. OUP USA. p. 536. ISBN 978-0-19-992305-2.