| 1966 Five Nations Championship | |
| Date: | 15 January - 26 March 1966 |
| Countries: | |
| Count: | 15 |
| Matches: | 10 |
| Tries: | 21 |
| Top Point Scorer: |  Claude Lacaze (14) |
| Top Try Scorer: | Christian Darrouy (2) Sandy Hinshelwood (2) David Whyte (2) Ken Jones (2) |
| Previous Year: | 1965 |
| Previous Tournament: | 1965 Five Nations Championship |
| Next Year: | 1967 |
| Next Tournament: | 1967 Five Nations Championship |
The 1966 Five Nations Championship was the thirty-seventh series of the rugby union Five Nations Championship. Including the previous incarnations as the Home Nations and Five Nations, this was the seventy-second series of the northern hemisphere rugby union championship. Ten matches were played between 15 January and 26 March. It was contested by England, France, Ireland, Scotland and Wales.
Wales won their 15th title, with a single loss, while England finished in a disappointing fifth and last place.
The teams involved were:
| Nation | Venue | City | Head coach | Captain | |
|---|---|---|---|---|---|
| Twickenham | London | none | Budge Rogers | ||
| Stade Olympique Yves-du-Manoir | Colombes | Jean Prat | Michel Crauste | ||
| Lansdowne Road | Dublin | none | Ray McLoughlin/Tom Kiernan | ||
| Murrayfield | Edinburgh | none | Stewart Wilson/Ian Laughland | ||
| National Stadium | Cardiff | none | Alun Pask/David Watkins |