Koenen is a patronymic surname of Low German ( ['køːnən]) or Dutch ( ['kunən]) origin derived from the given name Koen (Conrad).
Notable people with the surname include:
Adolf von Koenen (1837–1915), German geologist
Mathias Koenen (1849–1924), German civil engineer
Wilhelm Koenen (1886–1963), Communist and East German politician
Bernard Koenen (1889–1964), Communist and East German politician
Theo Koenen (1890–1964), German footballer
Joannes Henricus Maria Koenen (1893–1956), Dutch neurologist who described Koenen's tumor
Emmy Damerius-Koenen (1903–1987), East German politician
Heinrich Koenen (1910–1945), German anti-fascist fighter and Soviet agent
Ludwig Koenen (born 1931), German-born American philologist and papyrologist
Gerd Koenen (born 1944), German historian and former communist
Lyle Koenen (born 1956), American politician in Minnesota
Vera Koenen (born 1967), Dutch volleyball player
Michael Koenen (born 1982), American football player
