1966 NSW Federation Cup

The 1966 NSW Federation Cup (Henry Seamonds Trophy) was the tenth and final edition of the NSW Soccer Federation's premier soccer cup. The cup was open to all ten clubs in the first and six second division clubs.

Sydney Hakoah were the defending champions, but were eliminated by St. George Budapest in the semi-finals when they lost 1–2.

The final was played on 22 May 1966 between APIA Leichhardt and St. George Budapest, with APIA winning the match 3–2 to claim their second Federation Cup title.

First Round
The First Round saw all ten First Division and the top 6 Second Division clubs from the previous season participate.

Final

 * style="vertical-align:top;width:50%"|