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.