The 1966 Icelandic Cup was the seventh edition of the National Football Cup.
It took place between 16 July 1966 and 23 October 1966, with the final played at Melavöllur in Reykjavík. The cup was important, as winners qualified for the UEFA Cup Winners' Cup (if a club won both the league and the cup, the defeated finalists would take their place in the Cup Winners' Cup). Teams from the Úrvalsdeild karla (1st division) did not enter until the quarter-finals. In prior rounds, teams from the 2. Deild (2nd division), as well as reserve teams, played in one-legged matches. In case of a draw, the match was replayed.
KR Reykjavík won their 6th Cup in 7 seasons, beating the Icelandic champions, Valur Reykjavík, 1 - 0 in the final.
