Marwell (21 May 1978 – October 2003) was an Irish-bred, British-trained Thoroughbred racehorse and broodmare. A specialist sprinter, she won ten of her thirteen races, including several against colts and older horses, and was the highest-rated filly of her generation in Europe at both two and three years of age. She won all five of her races as a two-year-old in 1980, including the Molecomb Stakes, Flying Childers Stakes, and Cheveley Park Stakes. In the following year, she was beaten over a mile in the classic 1000 Guineas but returned to sprinting to win the King's Stand Stakes July Cup and Prix de l'Abbaye. She was retired from racing at the end of 1981 and became a successful broodmare. Marwell died in 2003.