The 1965–66 Greek Football Cup was the 24th edition of the Greek Football Cup. For the second time in three editions, the Cup final was scratched: AEK Athens were awarded the Cup as the HFF was late to determine a date for the match. Due to Olympiacos having to prepare for the next season's European Cup, the delay meant that Olympiacos would not be able to field a team for the final.

Calendar

From Round of 32 onwards:

Knockout phase

In the knockout phase, teams play against each other over a single match. If the match ends up as a draw, extra time will be played. If a winner doesn't occur after the extra time the winner emerges by a flip of a coin. The mechanism of the draws for each round is as follows:

Bracket

Round of 32

Round of 16

Quarter-finals

Semi-finals

Final

The final was scratched and AEK Athens were awarded the Cup as Olympiacos were unable to participate due to their preparation for the next season's European Cup, following the HFF being late to determine a date for the match.