Judith Madan (née Cowper; 26 August 1702 – 7 December 1781) was an English poet. She was the granddaughter of Lady Sarah Cowper (1644–1720), the diarist.
She was the daughter of lawyer Spencer Cowper, Justice of the Common Pleas, and his wife Pennington, and is thought to have been born at the family seat, Hertingfordbury Park, Hertfordshire, England. As Judith Cowper she corresponded with Alexander Pope, whom she probably met.
In 1723 Cowper married Colonel Martin Madan, groom of the bedchamber to Frederick, Prince of Wales, and MP for Wootton Basset. He died at Bath on 4 March 1756, aged 53. Their sons included Rev. Martin Madan, author of Thelyphthora a defence of polygamy, and the Right Rev. Spencer Madan, bishop successively of Bristol and Peterborough. Their elder daughter, Maria Frances Cecilia, married William Cowper of Hertingfordbury, her first cousin; a volume of Frances Maria Cowper's religious verse, attributed to "a lady" and revised by her famous poet cousin, was published in 1792. Their younger daughter, Penelope (died 22 December 1805), became the wife of General Sir Alexander Maitland (1728–1820). Judith was the aunt of William Cowper the English poet and hymnodist, and grandmother of General Frederick Maitland. She died at Stafford Row, Westminster on 7 December 1781.
- Abelard to Eloisa - 1720
- The Progress of Poetry - 1721
- Verses on the Death of Mr. Hughes, 1719-30
- William Prideaux Courtney: Dodsley's Collection of Poetry(1910)
- Whitwell Elwin, Works of Pope, ed. Elwin and Courthope (1871-1889)