Nelson was a three-sport athlete at Anoka High School , Anoka, MN, earning letters in football, basketball and baseball. As a senior, Nelson was selected as captain, team MVP and to the all-state team in football. Nelson then went on to college at North Dakota State University and graduated from NDSU in 1974 after being named a two-time All-American, team captain and MVP in football.
He was selected by the Patriots in the 2nd round of the 1974 NFL Draft and missed only three games during his 14-year NFL career in which he was named team MVP twice. He was selected to the Pro Bowl three times in 1980, 1984, and 1985 and his #57 jersey was retired by the Patriots. He is credited with helping the Patriots reach Super Bowl XX versus the Chicago Bears.
Steve Nelson played linebacker for the Patriots from 1974–87 and became the nucleus of the Patriots defense. Nelson was voted to three Pro Bowls and recorded more than 100 tackles nine times during his career. He led the Patriots in tackles in eight of his 14 seasons, including an unofficial team record of 207 in 1988. He finished his career with a patriotic 1,776 total tackles. After retirement, he coached for the Patriots and later built Curry College into a perennial power. In 1993, Nelson was inducted into the Patriots Hall of Fame.
More recently, Nelson has become a familiar football analyst on local television and radio. He currently works as a business development executive for Lighthouse Computer Services, Inc., a Lincoln, RI-based technology company. In September, 2011, Nelson was named to the inaugural class of the Anoka High School Hall of Fame.