Heun is a German surname. Notable people with the surname include:

• Conor Heun (born 1979), American mixed martial artist
• Carl Heun, (1771–1854), German author, better known by his pseudonym Heinrich Clauren
• Dirk Heun (born 1953), German footballer
• Dustin Heun (born 1984), German footballer
• Jürgen Heun (born 1958), East German footballer
• Karl Heun (1859–1929), German mathematician
• Wilhelm Heun (1895–1986), German Wehrmacht general
• John Heun, (born 1974), American Human Resources Executive

• Heun, Nebraska