The 1965–66 National Hurling League was the 35th season of the National Hurling League.
Tipperary came into the season as defending champions of the 1964-65 season. Laois joined Division 1 as the promoted team.
On 18 September 1966, Kilkenny won the title after a 10-15 to 2-15 aggregate win over New York in the final. It was their 3rd league title overall and their first since 1961-62.[1]
In spite of finishing at the bottom of their respective groups, neither Galway of Laois were relegated.
Tipperary's Jimmy Doyle was the Division 1 top scorer with 4-20.
Semi-finals
Home final
Finals
On 24 April 1966, Offaly won the title after a 4-11 to 3-9 win over Kerry in the final.
Semi-finals
Final
On 9 October 1966, Mayo won the title after a 1-12 to 1-8 win over Armagh in the final.
Semi-final
Final