The 1966 United States Road Racing Championship season was the fourth season of the Sports Car Club of America's United States Road Racing Championship. It began April 24, 1966, and ended September 4, 1966, after eight races. GT cars were dropped from the program; only the two sports car classes were run. Chuck Parsons won the season championship.
| Rnd | Race | Length | Circuit | Location | Date | |
|---|---|---|---|---|---|---|
| 1 | Stardust Grand Prix | 180miles | Stardust International Raceway | Las Vegas, Nevada | April 24 | |
| 2 | Riverside 300 | 300km (200miles) | Riverside International Raceway | Riverside, California | May 1 | |
| 3 | Monterey 150 | 150miles | Laguna Seca Raceway | Monterey, California | May 8 | |
| 4 | Bridgehampton 200 | 200miles | Bridgehampton Race Circuit | Bridgehampton, New York | May 22 | |
| 5 | Sports Car Grand Prix at Watkins Glen | 200miles | Watkins Glen Grand Prix Race Course | Watkins Glen, New York | June 26 | |
| 6 | Pacific North West Grand Prix | 250km (160miles) | Pacific Raceways | Kent, Washington | July 30 | |
| 7 | Buckeye Cup | 200miles | Mid-Ohio Sports Car Course | Lexington, Ohio | August 28 | |
| 8 | Road America 500 | 500miles | Road America | Elkhart Lake, Wisconsin | September 4 |
Overall winner in bold.
| Rnd | Circuit | Over 2.0 Winning Team | Under 2.0 Winning Team | Results |
|---|---|---|---|---|
| Over 2.0 Winning Driver(s) | Under 2.0 Winning Driver(s) | |||
| 1 | Stardust |
| Results | |
 John Cannon |  Ken Miles | |||
| 2 | Riverside |
| Results | |
 John Fulp | Scooter Patrick | |||
| 3 | Laguna Seca |
| Results | |
| Charlie Hayes | Ken Miles | |||
| 4 | Bridgehampton |
| Results | |
| Jerry Grant | Scooter Patrick | |||
| 5 | Watkins Glen |
| Results | |
| John Fulp | Ralph Trieschmann | |||
| 6 | Kent |
| Results | |
| Mark Donohue | Don Wester | |||
| 7 | Mid-Ohio |
| Results | |
| Lothar Motschenbacher | Joe Buzzetta | |||
| 8 | Road America |
|
| Results |
| Chuck Parsons | Joe Buzzetta Günter Klass |