Nils Johan Semb (born 24 February 1959) was the coach of the Norwegian national football team from 1998 to 2003, presiding over 68 matches.
He led his team to the 2000 European Football Championship (a first for Norway). Though successful, at least in the beginning of his tenure, he drew heavy criticism for his team's defense-oriented style, where long balls, counter-attacks and direct passes were hallmarks of their attacking style. He was replaced by Åge Hareide in 2003. He was a commentator for the Norwegian TV channel TV 2, but resigned in 2009 to become the Chief of Elite Football at the Football Association of Norway.
He has his education from the Norwegian School of Sport Sciences.