She was the fourth and youngest daughter of the architect Edwin Lutyens, and his wife Emily Bulwer-Lytton. Emily was the daughter of Robert Bulwer-Lytton, Viceroy of India, and the granddaughter of the novelist-peer Edward Bulwer-Lytton. As a child Mary spent time with her maternal grandmother Edith, the former vicereine, who lived at Knebworth some 30 miles from London.
In the 1920s, her father was working on his buildings at Delhi. Mary visited India with her mother and went to Australia, staying at The Manor, a centre run by Charles Webster Leadbeater in Mosman, New South Wales, while Krishnamurti and his brother Nitya stayed at another house nearby. Lutyens stayed there for some time, which eventually provided her with material for her book Krishnamurti: The Years of Awakening.
Apart from her works on Krishnamurti, Lutyens also wrote a number of novels, and biographies of John Ruskin, Effie Gray and her own family. In her book Millais and the Ruskins she put forward the controversial argument that Ruskin could not consummate his marriage because he was repelled by his wife's pubic hair.
Mary Lutyens married twice. Her first marriage, in 1930, to Anthony Rupert Herbert Franklin Sewell, a stockbroker, produced one daughter, Amanda Lutyens, but ended in divorce in 1945. Her second marriage, in 1945, was to J. G. Links, art historian and royal furrier, and ended with his death in 1997.
- Perchance to Dream, London: John Murray, 1935.
- Effie in Venice: Effie Ruskin's Letters Home 1849–1852, London: John Murray, 1965, Pallas Athene (UK), 2001 edition: ISBN 1-873429-33-9.
- Millais and the Ruskins, London: John Murray, 1967, Vanguard Press in USA.
- Krishnamurti: The Years of Awakening, London: John Murray, 1975, Shambhala Publications reprint edition 1997: ISBN 1-57062-288-4. First installment of a three-volume biography, covers the period from Krishnamurti's birth in 1895 to 1933.
- Krishnamurti: The Years of Fulfilment, London: John Murray, 1983, ISBN 0-7195-3979-X, Farrar, Straus, Giroux paperback: ISBN 0-374-18224-8, Avon Books 1991 reprint with US spelling "Fulfillment": ISBN 0-380-71112-5. Second volume of the Krishnamurti biography, covers the years from 1933 to 1980.
- Krishnamurti: The Open Door, London: John Murray, 1988, ISBN 0-7195-4534-X. Final volume of biography covers years 1980 to 1986, the end of Krishnamurti's life.
- The Lyttons in India: An account of Lord Lytton's Viceroyalty, 1876–1880 London: John Murray, 1979, ISBN 0-7195-3677-4.
- Edwin Lutyens: A Memoir, Academic Pr Canada Ltd, 1980, ISBN 0-7195-3777-0, Black Swan, 1991 revised edition: ISBN 0-552-99417-0.
- The Life and Death of Krishnamurti, London: John Murray, 1990, ISBN 0-7195-4749-0, Nesma Books India 1999: ISBN 81-87075-44-9, ISBN 0-900506-22-9, also published as Krishnamurti: His Life and Death, St Martins Press 1991: ISBN 0-312-05455-6, an abridgement of her trilogy on Krishnamurti's life.
- The Boy Krishna, 1995, Krishnamurti Foundation Trust paperback: ISBN 0-900506-13-X. Subtitled, "The First Fourteen Years in the Life of J. Krishnamurti".
- Krishnamurti and the Rajagopals, 1996, Ojai, CA: Krishnamurti Foundation of America, ISBN 1-888004-08-8.
- J. Krishnamurti: A Life, 2005, Penguin Books India, ISBN 0-14-400006-7. This book is a compilation of The Years of Awakening, The Years of Fulfilment, and The Open Door.
- Sarah Anderson. Obituary: Mary Lutyens The Independent, 13 April 1999.
- Eric Page. Obituary: Mary Lutyens, English Editor, Novelist and Biographer, 90 The New York Times, 17 April 1999.