The poll also named Norfolk-based Lotus as the most popular British manufacturer, with seven of its models making the 100 best British cars list.
Following the Mini at the top was the McLaren F1, according to a survey of Autocar readers. Jaguar and Ford both had six cars in the top 100, including the Jaguar D-type and the Ford Sierra RS Cosworth. Aston Martin had five, including the DB5 - a favourite with 007 James Bond.
Designed by Sir Alec Issigonis, the Mini achieved worldwide fame, being dubbed the first "classless car". The marque was successfully revived in a larger and more-powerful version by BMW in 2003.
Chas Hallett, of Autocar, said: "The Mini is associated with Great Britain around the world. In many ways, it was ahead of its time. It ensured a fabulous drive every time. Good examples are now worth tens of thousands of pounds."
The top 10 was: 1. Original Mini; 2. McLaren F1; 3. Jaguar E-type; 4. Range Rover; 5. Yamaha Motiv.E; 6. McLaren P1; 7. Jaguar XJ220; 8. Aston Martin DB5; 9. TVR Griffith; 10. Ford Escort Mexico.
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