Susan's Girl (1969–1988) was an American Thoroughbred racehorse.
Susan's Girl was bred and owned by Fred W. Hooper. Hooper was born poor on a Southern farm and eventually became rich enough to buy, breed, and run some of the best Thoroughbred horses of his day. His first purchase was Hoop Jr., named after his son, and winner of the 1945 Kentucky Derby. Over the years, Hooper built up a successful stable.
Racing as a two-year-old in 1971, Susan's Girl came up against a top filly called Numbered Account. As a three-year-old, Susan's Girl began to win races, taking nine out of her thirteen starts and never finishing out of the money. That year she was the American Champion Three-Year-Old Filly when Secretariat took both the male honors as well as becoming Horse of the Year.
At four, racing on both coasts, Susan's Girl won over $500,000.
By the end of the racing season in 1973, Hooper's filly was second only to the filly Shuvee in career earnings. Hooper wanted to see his filly become the first distaffer to win a million dollars. But in February 1974, she chipped a bone in her left foreleg. Hooper sent her to the noted equine surgeon Dr. Robert Copelan. Copelan removed three chips, then sent her home to Hooper's Farm in Ocala, Florida. For two months, Susan's Girl swam in the nearby Lake Weir every day. After nine months, she recovered and returned to the races.
At the age of five, Susan's Girl made a comeback. During her recovery, two females had passed the million dollar mark (Dahlia and Allez France), but these were European records. Hooper still hoped for the American record. In November 1974, Susan's Girl won the Falls City Handicap. In 1975, at the age of six, she had her best season in terms of earnings, winning six stakes and placed in eight. In the Matchmaker Stakes in Atlantic City, New Jersey, she set a track record. She beat males as well as older females and made her million plus dollars.