Boysen is a surname. Notable people with the surname include:
Audun Boysen (1929–2000), Norwegian middle-distance runner Ben Lukas Boysen (born 1981), German musician Bill Boysen (1936–2020), American artist Bjørn Boysen (1943–2018), Norwegian organist and educator David Boysen (born 1991), Danish footballer George E. Boysen (1890–1967), American politician Gudrun Boysen (born 1939), Danish physician Hans-Jürgen Boysen (born 1957), German football player and manager Harold Koch Boysen (1891–1963), American World War I flying ace Harro Schulze-Boysen (1909–1942), German resistance fighter against the Nazi regime Karsten Boysen (born 1938), Venezuelan sailor Lia Boysen (born 1966), Swedish actress Libertas Schulze-Boysen (1913–1942), German resistance fighter against the Nazi regime (born 1954), German actor Rasmus Boysen (born 1992), Danish retired handball player Rudolph Boysen (1895–1950), American horticulturist who created the boysenberry Sarah Boysen (born 1949), American psychology professor and primate researcher