Günter Kilian, twin brother of Horst Kilian, played for the West German water polo team that finished 10th at the 1968 Mexico City Olympics, losing 7-5 to Spain in the final round. The team also came in sixth eight years later in Montréal. The goalkeeper won a gold medal at the 1981 Europeans in Split and a bronze medal at the 1982 Worlds in Guayaquil. In total, he earned 213 international caps between 1968 and 1982. Between 1970 and 1978 Kilian helped SV Würzburg 05 to win five West German national titles (1970, 1974, and 1976-78). By profession, he was a policeman.