Stein Eriksen emerged on the national scene in 1947, aged 19, when he won the downhill and combination at the Holmenkollen Kandahar event. He was Norwegian Champion six times in the period 1949-54. His international breakthrough came in the World Championships at Aspen, Colorado in 1950, when he won the bronze medal in slalom. At the Oslo Olympics in 1952 Eriksen won the gold medal in giant slalom and silver in slalom, being the first skier from a country outside the Alpine region to win an Olympic gold medal in alpine skiing. He had a great season in 1954, when he won three gold medals at the Alpine World Championships in Åre, Sweden.
After the 1954 season Eriksen ended his amateur career and moved to Utah, USA, working as a ski instructor and headmaster of Ski Schools. Eriksen started as a ski instructor at Sun Valley in Idaho. He later established ski schools at various resorts, including Boyne Mountain, Michigan; Sugarbush in Vermont; Heavenly Valley, California; Snowmass and Aspen in Colorado; and Park City, Utah. Eriksen eventually settled at Deer Valley, Utah, where the Stein Eriksen Lodge was established in his name, living there until his death. Stein Eriksen became Norway’s first star in alpine skiing, and made alpine skiing popular in Norway. He was born in Oslo into a sport family. His father Marius Eriksen, Sr. won a bronze medal in team gymnastics at the Stockholm Games in 1912, and his brother Marius Eriksen, Jr. was Norwegian Champion in slalom and competed in the 1948 Winter Olympic Games at St. Moritz.