Denis is a masculine given name. Notable people with the name include:
Denis Diderot, French philosopher and co-founder of the EncyclopédieDenis Glushakov, Russian footballerDenis Grachev (fighter), Russian boxer, kickboxer and mixed martial artistDenis Grachev (badminton), Russian badminton playerDenis Hayes, environmentalist and Earth Day founderDenis Healey (born 1917), British politicianDenis Irwin, former Manchester United defenderDenis King, British composerDenis Kolodin, Russian footballerDenis Laktionov, Russian footballerDenis Law, former Manchester United centre-forwardDenis Leary, American actor and comedianDenis Lebedev, Russian boxerDenis Lebrun, comic artist (Blondie strip)Denis Marconato, Italian basketball playerDenis McDonough, American politician, appointed President Obama's second-term Chief of StaffDenis Perera (1930-2013), 8th Commander of the Sri Lanka ArmyDenis Shapovalov (born 1999), Canadian tennis playerDenis Smith, English cricketerDenis Stracqualursi, Argentine footballerDenis Tahirović (born 1985), Croatian footballerDenis Thatcher (1915–2003), British businessman, husband of former British Prime Minister Margaret ThatcherDenis Zvizdić (born 1964), Bosnia and Herzegovina politician, Chairman of the Council of Ministers