| Belmont Stakes | |
| Grade I stakes race | |
 Secretariat on the final stretch | |
| Location | Belmont Park Elmont, New York, U.S. |
|---|---|
| Date | June 9, 1973 |
| Distance | 1+1⁄2 mi (12 furlongs; 2,414 m) |
| Winning horse | Secretariat |
| Winning time | 2:24 |
| Jockey | Ron Turcotte |
| Trainer | Lucien Laurin |
| Owner | Penny Chenery |
| Conditions | Fast |
| Surface | Dirt |
| Attendance | 69,138 |
The 1973 Belmont Stakes was the 105th running of the Belmont Stakes at Belmont Park in Elmont, New York, held on June 9, 1973. Facing a field of five horses, Secretariat won by 31 lengths going away (had the race been longer he would have won by even more), the largest margin of victory in Belmont history, in front of a crowd of 69,138 spectators. His winning time of 2 minutes and 24 seconds still stands as the American record for a mile and a half on dirt. The event was televised and broadcast over the radio.
Secretariat was widely viewed as the favorite to win by most sportswriters and people; however, the added distance and the possibility of running too slow for a distance or running too fast too soon could potentially cause him to lose. Out of the starting gate, Secretariat and Sham traded the lead. Around the three-quarters mile marker Sham began to fade and Secretariat began to extend an advantage. Twice a Prince and My Gallant overtook Sham to take second and third, respectively. Sham finished last, behind Pvt. Smiles, who was in last before Sham slowed severely.
The victory in the Belmont, when combined with Secretariat's previous victories in the Kentucky Derby and the Preakness Stakes, meant he completed the Triple Crown of Thoroughbred Racing. This was significant, as Secretariat became the ninth horse to complete the feat and broke a 25-year drought where no horse had completed the achievement.