Diesen is a surname. Notable people with the surname include:
Deborah Diesen, American children's book author Einar Diesen (1897–1994), Norwegian journalist and newspaper editor Emil Diesen (1880–1942), Norwegian civil servant and editor Erik Diesen (1922–1999), Norwegian revue writer and radio and television personality Erling Diesen (born 1932), Norwegian engineer and civil servant Ernst Diesen (1913–1970), Norwegian actor and theatre director Henry Diesen (1883–1953), Norwegian naval officer Kari Diesen (1914–1987), Norwegian singer and revue actress Mark Diesen (1957–2008), American chess player Sverre Diesen (born 1949), Norwegian military officer Thorstein Diesen (1862–1925), Norwegian barrister, newspaper editor and politician Trygve Allister Diesen (born 1967), Norwegian director, producer, and screenwriter