Joachim Mattern (born May 2, 1948 in Beeskow) is an East German sprint canoer who competed in the 1970s. Competing in two Summer Olympics, he won two medals at Montreal in 1976 with a gold in the K-2 500 m and silver in the K-2 1000 m events.Mattern also won five medals at the ICF Canoe Sprint World Championships with a gold (K-2 500 m: 1977), two silvers (K-2 1000 m: 1977, K-4 1000 m: 1970), and two bronzes (K-2 1000 m: 1970, 1973).