The inaugural Singapore Grand Prix was held from 9 to 11 April 1966, on the Thomson Road Grand Prix circuit. Previous editions of the Grand Prix were held before Singapore gained its independence, and were not called Singapore Grand Prix. The 1965 Malaysian Grand Prix was held on the same course, as part of the Malaysian Grand Prix event, as the 1966 Grand Prix of Singapore.
1966 1ST SINGAPORE GRAND PRIX Thomson Road Grand Prix circuit
| Singapore GP | ||||
|---|---|---|---|---|
| MOTORCYCLE GRAND PRIX | 60 laps | |||
| Rank | Rider | Country | Motorcycle | Time |
| 1. | Mitsuo Ito |  Japan | Suzuki 125 | 2h 37min 16.6s |
| SPORTS CAR & GT CARS RACE | 15 laps | |||
| Rank | Driver | Country | Car | Time |
| 1. | Lee Han Seng |  Singapore | Lotus-Ford Twin Cam | 39min 13.3s |
| SPORTS CAR & GT CARS RACE | 15 laps | |||
| Rank | Driver | Country | Car | Time |
| 1. | Albert Poon |  Hong Kong | Lotus Cortina 1500 | 39min 13.3s |
| SINGAPORE GRAND PRIX | 60 laps | |||
| Rank | Driver | Country | Car | Time |
| 1. | Lee Han Seng | Singapore | Lotus 22 | 2h 29min41.8s |