She was born in Winchester on 12 December 1948 into a prominent Hampshire family. Her grandmother, Sybil Tufnell, was the first woman in the UK to run a firm of estate agents, and her father was a naval captain who served in the Far East and Australia.
She rode her mother's novice mare, Scorched Earth, to victory in the Goya Stakes at Kempton Park on 6 May 1972, the first ever ladies' flat race held under Jockey Club rules. Neither horse nor jockey had raced previously. The race was the first in a twelve race series for female jockeys, and with three winners from seven rides, Tufnell was the series champion.
She continued to ride competitively until 1974, including in the first mixed race, at Nottingham, in March 1974, and founded the Lady Jockeys' Association of Great Britain, the first such body in the world, after a meeting at Haydock.
She was appointed MBE in 1976, a year after retiring from race riding. She opened an equestrian yard and became an instructor, and later went on to train point-to-pointers and hunter chasers with her husband, trainer Glenn Humphrey, who she married in 1983. The couple separated in 1994.
- Goldman, Laurence (2013). Oxford Dictionary of National Biography. Oxford: OUP. ISBN 0199671540.
- Kay, Joyce; Vamplew, Professor Wray (2005). Encyclopedia of British Horse Racing. New York: Routledge. p. 343. ISBN 978-0714682921.
- "Meriel Tufnell". Daily Telegraph. 17 October 2002. Retrieved 5 November 2013.
- "Sparks". Retrieved 5 November 2013.