| Sun Stream | |
|---|---|
| Sire | Hyperion |
| Grandsire | Gainsborough |
| Dam | Drift |
| Damsire | Swynford |
| Sex | Mare |
| Foaled | 1942 |
| Country | United Kingdom |
| Colour | Chestnut |
| Breeder | Edward Stanley, 17th Earl of Derby |
| Owner | Edward Stanley, 17th Earl of Derby |
| Trainer | Walter Earl |
| Record | 7: 5–1–1 |
| Earnings | £15,670 |
| Major wins | |
| Queen Mary Stakes (1944) 1000 Guineas (1945) Epsom Oaks (1945) | |
Sun Stream (1942 – January 1959) was a British Thoroughbred racehorse and broodmare, best known for winning two Classics in 1945. The filly won five times from seven races in a track career which lasted from spring 1944 until June 1945. As a two-year-old in 1944 she won three races including the Queen Mary Stakes. After being beaten on her three-year-old debut she won the 1000 Guineas over one mile at Newmarket and a substitute Oaks over one and a half miles at the same course a month later. After her second classic win she was retired to stud, where her record as a broodmare was disappointing.