Viktor Nikolaevich Denisov (Russian: Виктор Николаевич Денисов), best known by the shortened pseudonym Viktor Deni, (8 March 1893 – 3 August 1946) was a Russian satirist, cartoonist and poster artist. Deni was one of the major agitprop poster artists of the Bolshevist period (1917–1921).
Born in Moscow in 1893, Denisov later shortened his surname to Deni. Deni moved to St. Petersburg in 1913 where he established himself as a successful caricaturist, his caricatures appearing in a number of illustrated satirical journals. After the October Revolution Deni worked for the Litizdat (the state publishing house), an agency founded in June 1919 to coordinate the various publishing centres on behalf of the Bolsheviks. He produced nearly 50 political posters during the Russian Civil War, including some of his most well known satirical work. He became one of the major agitprop poster artists of the Bolshevist period (1917–1921). Deni subsequently focused on producing newspaper cartoons that addressed foreign policy issues. During the German-Soviet War (World War II), he returned to the medium of the political poster together with several other prominent poster artists of the Civil War such as Mikhail Cheremnykh and Dmitri Moor.