The 1951 Isle of Man Tourist Trophy was the third round of the 1951 Grand Prix motorcycle racing season.
| Rank | Rider | Team | Speed | Time | |
|---|---|---|---|---|---|
| 1 | Geoff Duke | Norton | 150.97 km/h | 2.48.56.8 | |
| 2 |  Bill Doran | AJS | 147.12 km/h | 2.53.19.2 | |
| 3 | Cromie McCandless | Norton | 145.34 km/h | 2.55.27.0 | |
| 4 | Tommy McEwan | Norton | 139.75 km/h | 3.02.26.6 | |
| 5 |  Manliff Barrington | Norton | 138.55 km/h | 3.04.03.4 | |
| 6 | Len Parry | Norton | 138.21 km/h | 3.04.30.2 | |
| 7 | Eric Briggs | Norton | 137.78 km/h | 3.05.04.6 | |
| 8 | Albert Moule | Norton | 136.12 km/h | 3.07.20.0 | |
| 9 | Len Perry | Norton | 136.04 km/h | 3.07.26.0 | |
| 10 | Les Dear | Norton | 135.37 km/h | 3.08.22.4 |
| Rank | Rider | Team | Speed | Time | |
|---|---|---|---|---|---|
| 1 | Geoff Duke | Norton | 144.65 km/h | 2.56.17.6 | |
| 2 | Johnny Lockett | Norton | 141.99 km/h | 2.59.35.0 | |
| 3 | Jack Brett | Norton | 141.38 km/h | 3.00.24.4 | |
| 4 | Mick Featherstone | AJS | 138.89 km/h | 3.03.35.8 | |
| 5 | Bill Lomas | Velocette | 138.5 km/h | 3.04.05.6 | |
| 6 | Bob Foster | Velocette | 137.94 km/h | 3.04.51.6 | |
| 7 | Cromie McCandless | Norton | 137.46 km/h | 3.05.31.0 | |
| 8 |  Rod Coleman | AJS | 137.18 km/h | 3.05.53.4 | |
| 9 | Ray Amm | Norton | 137.07 km/h | 3.06.01.8 | |
| 10 | Les Graham | Velocette | 136.85 km/h | 3.06.21.0 |
| Rank | Rider | Team | Speed | Time | |
|---|---|---|---|---|---|
| 1 | Tommy Wood | Moto Guzzi | 130.96 km/h | 1.51.15.8 | |
| 2 |  Dario Ambrosini | Benelli | 130.8 km/h | 1.51.24.2 | |
| 3 | Enrico Lorenzetti | Moto Guzzi | 126.71 km/h | 1.55.00.0 | |
| 4 | Wilfred G. Hutt | Moto Guzzi | 123.7 km/h | 1.57.48.8 | |
| 5 | Arthur Wheeler | Velocette | 120.85 km/h | 2.00.39.0 | |
| 6 | Fron Purslow | Norton | 118.99 km/h | 2.02.28.4 | |
| 7 |  Svend Aage Sørensen | Excelsior | 114.06 km/h | 2.07.44.8 | |
| 8 | Frank Cope | AJS | 112.63 km/h | 2.09.22.0 | |
| 9 | Arnold W. Jones | Excelsior | 109.81 km/h | 2.12.40.8 | |
| 10 | Harold Hartley | Rudge | 109.28 km/h | 2.13.20.0 |
| Rank | Rider | Team | Speed | Time | |
|---|---|---|---|---|---|
| 1 | Cromie McCandless | Mondial | 120.43 km/h | 1.00.30.0 | |
| 2 | Carlo Ubbiali | Mondial | 119.68 km/h | 1.00.52.4 | |
| 3 | Gianni Leoni | Mondial | 115.08 km/h | 1.03.19.8 | |
| 4 | Nello Pagani | Mondial | 112.76 km/h | 1.04.36.6 | |
| 5 |  Juan S Bulto | Montesa | 102.11 km/h | 1.11.21.0 | |
| 6 | Jose M Llobet | Montesa | 98.44 km/h | 1.14.01.4 | |
| 7 | Eric V C Hardy | DOT | 93.1 km/h | 1.18.16.2 | |
| 8 | Howard A Grindley | DMW | 91.55 km/h | 1.19.34.6 | |
| 9 | Leslie D Caldecutt | BSA | 90.72 km/h | 1.20.19.0 | |
| 10 | Robert Holton | Pankhurst Special | 90.68 km/h | 1.20.24.6 |
| Rank | Rider | Team | Speed | Time | |
|---|---|---|---|---|---|
| 1 | Ken Arber | Triumph | 128.24 km/h | 1.53.37.6 | |
| 2 | Ivan B Wickstead | Triumph | 127.85 km/h | 1.53.57.6 | |
| 3 | John Draper | Triumph | 126.4 km/h | 1.55.17.0 | |
| 4 | Bob W C Ritchie | Norton | 126.1 km/h | 1.55.33.2 | |
| 5 | Harry Plews | Norton | 126.05 km/h | 1.55.36.2 | |
| 6 | Jack Wood | Norton | 124.75 km/h | 1.56.53.0 | |
| 7 | Bob A Rowbottom | Matchless | 123.7 km/h | 1.57.48.6 | |
| 8 | Russell Oldfield | Triumph | 123.14 km/h | 1.58.20.0 | |
| 9 | David C Birrell | Triumph | 122.24 km/h | 1.59.12.0 | |
| 10 | John N P Wright | BSA | 122.04 km/h | 1.59.24.0 |
| Rank | Rider | Team | Speed | Time | |
|---|---|---|---|---|---|
| 1 | Brian Purslow | BSA | 121.25 km/h | 2.00.10.0 | |
| 2 | Geoff E Read | Norton | 120.47 km/h | 2.00.56.6 | |
| 3 | John Draper | Norton | 120.24 km/h | 2.01.10.8 | |
| 4 | D N Bradshaw | Norton | 119.89 km/h | 2.01.33.2 | |
| 5 | Derek Farrant | BSA | 119.63 km/h | 2.01.48.4 | |
| 6 | D Carr | Norton | 118.44 km/h | 2.02.42.0 | |
| 7 | Stan T Cooper | Douglas | 116.57 km/h | 2.04.56.8 | |
| 8 | John Moore | BSA | 116.3 km/h | 2.05.18.4 | |
| 9 | C E Staley | BSA | 116.02 km/h | 2.05.32.2 | |
| 10 | Derek Morley | BSA | 115.75 km/h | 2.05.53.0 |