Johannessen is a Norwegian and Faroese patronymic surname. Notable people with the surname include:

• Astrid Johannessen (born 1978), Norwegian former football player who played for the Norway women's national football team
• Bjørnar Johannessen (born 1977), Norwegian football midfielder of Sparta Sarpsborg in the Norwegian First Division
• Guri Johannessen (1911–1972), Norwegian politician for the Labour Party
• Herman Horn Johannessen (born 1964), Norwegian sailor and Olympic medalist
• Johannes J. Johannessen, American Medal of Honor recipients
• Leif Erlend Johannessen (born 1980), Norwegian chess player, and Norway's fifth International Grandmaster
• Martha Frederikke Johannessen (1907–1973), Norwegian politician for the Labour Party
• Maurice Johannessen, American politician from California and a member of the Republican Party
• Otto Johannessen (1894–1962), Norwegian gymnast who competed in the 1920 Summer Olympics
• Pål Johannessen, Norwegian actor known for the role of Basse in the Norwegian Olsen Gang films
• Sigge Johannessen (1884–1974), Norwegian gymnast who competed in the 1908 Summer Olympics
• Sigurd Halvorsen Johannessen (1881–1964), Norwegian acting councilor of state in 1940–1941 and a minister 1941–1942
• Svein Johannessen (1937–2007), Norwegian chess player
• Trygve Johannessen (born 1953), Norwegian former footballer
• Ørjan Johannessen (born 1985), Norwegian chef, Bocuse d'Or Europe gold medallist
• Viggo Johannessen (1936–2012), Norwegian civil servant