Berg, who jumped for the club Stjørdals IL , made his debut in the Ski Jumping World Cup on December 30, 1983 at the Four Hills Tournament in Oberstdorf; he finished eighth in the overall tour. In the following three years he jumped only irregularly in the World Cup, but in his rare appearances he regularly achieved placements among the top ten.
In 1984 Berg became Norwegian champion on the large hill. At the Olympic Winter Games in Sarajevo he reached fifth place on the normal hill in the same year; he did not compete on the large hill. His most successful season was his last: In the winter of 1985/86 he finished fifth in the overall ranking of the Four Hills Tournament, and on February 19, 1986 he won his only World Cup victory in St. Moritz .
Berg is currently a trainer for Team Trønderhopp in Trondheim and looks after the elite team there.