Born in Malad City, Idaho, Andersen attended Utah State University, where he became a member of the Sigma Chi fraternity.

He was also invited and competed in the 1952 United States Men's Olympic Basketball Team tryouts in New York City.

During his tenure as the Aggies head coach, Utah State made four appearances in the NCAA basketball tournament including a trip to the Elite Eight in 1970, losing to eventual champion UCLA.

Andersen recommended Brown as his successor, but when USU officials rejected the idea, Brown went to Washington State for one season as an assistant before succeeding Press Maravich as LSU's coach, where he remained for 25 seasons (1972–97), compiling a 448–301 record.

Andersen held the post for ten years until he was lured back into coaching again in 1983 for Brigham Young University (BYU).