| Competition: | Serie A |
| Season: | 1965–66 |
| Dates: | 5 September 1965 – 22 May 1966 |
| Winners: | Internazionale 10th title |
| Relegated: | Sampdoria Catania Varese |
| Continentalcup1: | European Cup |
| Continentalcup1 Qualifiers: | Internazionale |
| Continentalcup3: | Inter-Cities Fairs Cup |
| Continentalcup3 Qualifiers: | Bologna Napoli Juventus |
| Continentalcup2: | Cup Winners' Cup |
| Continentalcup2 Qualifiers: | Fiorentina |
| League Topscorer: | Luís Vinício (25 goals) |
| Matches: | 306 |
| Total Goals: | 668 |
| Prevseason: | 1964–65 |
| Nextseason: | 1966–67 |
The 1965–66 Serie A season was won by Internazionale.
Brescia, Napoli and SPAL had been promoted from Serie B.
| Rank | Player | Club | Goals |
|---|---|---|---|
| 1 |  Luís Vinício | Vicenza | 25 |
| 2 |  Angelo Sormani | Milan | 21 |
| 3 | Sandro Mazzola | Internazionale | 19 |
| 4 | José Altafini | Napoli | 13 |
| Virginio De Paoli | Brescia | ||
| Cané | Napoli | ||
| 7 | Helmut Haller | Bologna | 12 |
| Harald Nielsen | Bologna | ||
| Angelo Domenghini | Internazionale | ||
| Giancarlo Salvi | Sampdoria | ||
| 11 | Luigi Riva | Cagliari | 11 |
| Enrico Muzzio | SPAL | ||
 Kurt Hamrin | Fiorentina |