The 1965–66 Cupa României was the 28th edition of Romania's most prestigious football cup competition.

The title was won by Steaua București against UTA Arad.

The competition is an annual knockout tournament.

In the first round proper, two pots were made, first pot with Divizia A teams and other teams till 16 and the second pot with the rest of teams qualified in this phase. Each tie is played as a single leg.

First round proper matches are played on the ground of the lowest ranked team, then from the second round proper the matches are played on a neutral location.

In the first round proper, if a match is drawn after 90 minutes, the game goes in extra time, and if the scored is still tight after 120 minutes, the team who played away will qualify.

From the second round proper, if a match is drawn after 90 minutes, the game goes in extra time, and if the scored is still tight after 120 minutes, then the younger team (the lower average of players age) will qualify.

From the first edition, the teams from Divizia A entered in competition in sixteen finals, rule which remained till today.

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