Madam Gay (25 February 1978 – 1983) was a British Thoroughbred racehorse. She showed some promise as a two-year-old in 1980 before developing into a top-class middle distance performer in the following year. Her only victory in a thirteen race career came when she won the Prix de Diane in 1981, but she was placed in many important races including the Oaks Stakes, King George VI and Queen Elizabeth Stakes, Arlington Million and Prix Vermeille. Having been originally bought for 8,000 guineas she was eventually sold for a reported $1.4 million.