Koeppen is a German surname. Notable people with the surname include:
Adolf Otto Koeppen (1902–1972), German painter
Andreas Koeppen (born 1961), German politician (SPD)
Hans Koeppen (1876–1948), German soldier and race driver
Jens Koeppen (born 1962), German politician (CDU)
Martina Koeppen (born 1967), German politician (SPD)
Werner Koeppen (1910–1994), German Nazi, assistant to Alfred Rosenberg
Wolfgang Koeppen (1906–1996), German author