Mary Fitton (or Fytton) (baptised 25 June 1578 – 1647) was an Elizabethan gentlewoman who became a maid of honour to Queen Elizabeth. She is noted for her scandalous affairs with William Herbert, 3rd Earl of Pembroke, Vice-Admiral Sir Richard Leveson, and others. She is considered by some to be the "Dark Lady" of Shakespeare's sonnets.