Mathiesen is a Danish-Norwegian patronymic surname meaning "son of Mathies" (equivalent of the Biblical Μαθθαιος, cf. English Matthew). Several spelling variants are used, including Matthiesen, Matthiessen, Mathisen, Matthisen. A similar diversity of forms exist for the parallel given name Mathias. There are several people with the surname Mathiesen:
Árni Mathiesen (b. 1958), Icelandic politician
Børge Mathiesen (1918–1962), Danish football player
Brian Vad Mathiesen, (b. 1978), Danish engineer and professor
Charles Mathiesen (1911–1994), Norwegian speed skater
Mathiesen family, a Norwegian business family, includning
Christian Pierre Mathiesen (1870–1953), Norwegian politician for the Conservative Party
Haagen Mathiesen (1759–1842), Norwegian timber merchant, ship-owner and politician.
Haaken C. Mathiesen (1827–1913), Norwegian landowner and businessperson
Haaken L. Mathiesen (1858–1930), Norwegian landowner and businessperson
Jørgen Mathiesen (1901–1993), Norwegian landowner and businessperson
Hein-Arne Mathiesen (b. 1971), Norwegian ski jumper
Mattis Mathiesen (b. 1924), Norwegian photographer and film director
Mihkel Mathiesen (1918–2003), Estonian politician
Niels Mathiesen (1829–1900), Norwegian politician and merchant
Pål Mathiesen (b. 1977), Norwegian musician
Per Mathiesen (1885–1971), Norwegian gymnast
Thomas Mathiesen (b. 1933), Norwegian sociologist
Matthiesen may refer to:
Leroy Matthiesen, Roman Catholic Bishop of Amarillo, Texas