Heun is a German surname. Notable people with the surname include:
Conor Heun (born 1979), American mixed martial artistCarl Heun, (1771–1854), German author, better known by his pseudonym Heinrich ClaurenDirk Heun (born 1953), German footballerDustin Heun (born 1984), German footballerJürgen Heun (born 1958), East German footballerKarl Heun (1859–1929), German mathematicianWilhelm Heun (1895–1986), German Wehrmacht general