The Brocklesby Stakes is a flat conditions race horse race in Great Britain open to horses aged two years. It is notable as the traditional opening two-year-old race of the British Flat racing season. It is run over five furlongs at Doncaster Racecourse.
The Brocklesby was first run in 1849 as an all-age 12 furlong race at the now defunct Carholme racecourse in Lincoln, but became a five furlong race for two-year-olds in 1875. It moved to Doncaster in 1965, where it appears on the same card as the Lincolnshire Handicap, also previously run at Carholme. Arguably the best horse to win the race was Donovan, in 1888. Donovan went on to win The Derby and the St Leger in 1889. Other top class horses to win the race have included Semolina, Deep Diver, Provideo, The Last Lion and Hearts of Fire.