The 1990–91 National Hurling League was the 60th season of the National Hurling League, the top league for inter-county hurling teams, since its establishment in 1925. The season began on 14 October 1990 and concluded on 12 May 1991. Kilkenny came into the season as defending champions of the 1989-90 season. Clare and Waterford entered Division 1 as the two promoted teams. On 12 May 1991, Offaly won the title after a 2-6 to 0-10 win over Wexford. It was their first league title ever.