Derring-Do (1961–January 1978) was a British Thoroughbred racehorse and sire. He was one of the leading British two-year-olds of 1963 when he won two of his three races including the Cornwallis Stakes. In the next two seasons, he developed into a top class racehorse over distances between seven and ten furlongs with his most important wins coming in the Hungerford Stakes, Valdoe Stakes, and Queen Elizabeth II Stakes. He was retired to stud at the end of his four-year-old season and became a successful breeding stallion.