The 1970 O'Byrne Cup was a Gaelic football tournament contested by the county teams of Leinster GAA. It was the first staging of the O'Byrne Cup competition.
Kildare won the delayed tournament after defeating Louth in the final, played at the Gaelic Grounds in Drogheda on 12 March 1972.
The tournament was contested on a knockout basis. First-round byes were awarded to Kildare, Longford, Offaly and Wicklow.