Werner Kiem had his first World Cup race in Falun in the individual event, and achieved his best result in 1989 in the relay in Ruhpolding with a fourth place. The peak of his career came at the 1988 Olympic Winter Games with a relay bronze medal. The same team had also won a bronze medal at the 1988 World Championships, in Oslo, where he had his best individual result internationally by placing fifth in the 20 km. Kiem also competed at the 1985 and 1987 World Championships but was not near the podium. In 1989 he came close to a relay medal again, when Italy placed fourth. His only Italian title came in 1986 and in 1987 he was second, both in the sprint. Kiem retired after the 1989 season.
Kiem later became Chairman of the luge club ASV Laces Raiffeisen and Vice-President of the Fédération Internationale de Luge de Course (FIL). As president of the organizing committee, he was responsible for the organization of the 2005 natural track luge World Cup in Laces. Kiem also managed the Hotel Latscherhof, which he inherited from his father.