Marghanita Laski was born in Manchester, England, to a prominent family of Jewish intellectuals (Neville Laski was her father, Moses Gaster her grandfather and Harold Laski her uncle), she was educated at Lady Barn House School in Manchester and St Paul's Girls' School in Hammersmith, worked in fashion, then studied English at Somerville College, Oxford  where she was a close friend of Inez Pearn, who was later to become a novelist and marry Stephen Spender and subsequently (following divorce) Charles Madge.
After her son and daughter were born, Laski began writing in earnest; most of her output in the 1940s and 1950s was fiction. She wrote the original screenplay of the 1952 British film "It Started in Paradise" and sold the film rights to one novel, Little Boy Lost (1949), about an Englishman on the search for his lost son in the ruins of post-war France to John Mills. However, when the film adaptation was released in 1953, she was upset that it had been turned into a musical starring Bing Crosby. She turned towards non-fiction in the 1960s and 1970s, producing works on Charlotte Mary Yonge, Jane Austen, George Eliot and Rudyard Kipling.
An omnivorous reader, from 1958 onward she became a prolific and compulsive contributor to the Oxford English Dictionary and by 1986 had "carded" around 250,000 quotations, making her (according to Ilan Stavans) "the supreme contributor, male or female, to the OED".
In the 1960s, Laski was the science fiction critic for The Observer. She was a member of the Annan Committee on broadcastingm between 1974 and 1977. She joined the Arts Council in 1979, was elected its Vice Chair in 1982, and served as chair of its Literature Panel between 1980 and 1984.
Anthony Boucher described her novella The Victorian Chaise Longue as "an admirably written book, highly skilled in its economic evocation of time, place and character -- and a relentlessly terrifying one." Ecstasy: A Study of Some Secular and Religious Experiences has been compared to The Varieties of Religious Experience by William James in its importance. Tory Heaven, a counterfactual novel depicting a Britain ruled by a rigidly hierarchical Conservative dictatorship and satirising middle-class attitudes towards the Attlee ministry, was described as "wickedly amusing" by Ralph Straus of The Sunday Times, and as "an ingeniously contrived and wittily told tale" by Hugh Fausset of the Manchester Guardian: writing about the book in 2018, David Kynaston called it a "highly engaging, beautifully written novel".
- Love on the Supertax (1944) comic novel
- Stories of Adventure (1946) 
- The Patchwork Book (1946) editor
- To Bed with Grand Music (1946), as Sarah Russell
- Victorian Tales for Girls (1947) editor
- Tory Heaven or Thunder on the Right (1948) political satire
- Little Boy Lost (1949) novel
- Toasted English (US edition of Tory Heaven) (1949)
- Mrs Ewing, Mrs Molesworth and Mrs Hodgson Burnett (1950) biography
- The Village (1952) novel (reprinted by Persephone Books in 2004).
"It Started in Paradise" (1952) film screenplay.
- The Victorian Chaise-longue (1953) novel (reprinted in 1999 by Persephone Books)
- The Tower (1955) short story
- Apologies (1955) caricature
- The Offshore Island (1959) play
- Ecstasy: a Study of Some Secular and Religious Experiences (1961) psychology
- A Chaplet for Charlotte Yonge (1965) editor with Georgina Battiscombe
- Jane Austen and Her World (1969) literary history
- God and Man (1971) with Metropolitan Anthony (Bloom) of Sourozh religion
- George Eliot and Her World (1973) literary history
- Kipling's English History (1974) Rudyard Kipling poems, editor
- Everyday Ecstasy (1980) psychology
- Ferry, the Jerusalem Cat (1983) story
- From Palm to Pine: Rudyard Kipling Abroad and at Home (1987) biography
- Common Ground: an Anthology (1989) editor
- To Bed with Grand Music (2001) (posthumous)
Republished by Persephone BooksEdit
- "MARGHANITA LASKI NOVELIST AND CRITIC; AT 72". Boston Globe. Highbeam. 8 February 1988. Archived from the original on 22 October 2012.
- "Laski, Marghanita [formerly Esther Pearl] (1915–1988)". Dictionary of National Biography. 3 October 2013. doi:10.1093/ref:odnb/39837. Retrieved 15 April 2018.
- Elizabeth Lake. Spanish Portrait. The Clapton Press, London. p. 226. ISBN 978-1-9996543-2-0.
- AP News Archive, 7 February 1988, "Marghanita Laski dies at 72", apnewsarchive.com; accessed 14 February 2016.
"She is survived by her husband, publisher John [Eldred] Howard, who founded the Cresset Press"
- Hastie, Scott (1993). Abbots Langley—a Hertfordshire Village. Abbots Langley Parish Council. ISBN 978-0-9520929-0-2.
- Charlotte Brewer (22 July 2010). "Examining the OED". Oxford University.
- Verónica Albin: On Dictionaries: A Conversation with Ilan Stavans, Translation Journal, Volume 9, No. 2, April 2005.
- Brian W. Aldiss, "Book Review," sfImpulse, October 1966, p. 19.
- "Marghanita Laski". National Portrait Gallery. Retrieved 17 July 2011.
- Christine Finn: Chapter Eight Archived 16 March 2007 at the Wayback Machine Stanford University
- "Recommended Reading," F&SF, October 1954, p.95.
- Kynaston, David (14 April 2018). "Tory Heaven: the forgotten 1948 novel that predicted a Conservative dystopia". New Statesman. Retrieved 15 April 2018.
- "Selected with an introduction by M. Laski. The Carved Cartoon. By Austin Clare.-The Little Doctor. By Darley Dale.-Finn the Wolfhound. By A. J. Dawson.-Bevis. By Richard Jefferies."--British Library catalogue
- Burchfield (2004)
- Burchfield, R.W. (2007). "Laski, Marghanita (1915–1988)". Oxford Dictionary of National Biography (online ed.). Oxford University Press. doi:10.1093/ref:odnb/39837. Retrieved 11 April 2012. (Subscription or UK public library membership required.)
- Marghanita Laski at Persephone Books
- Marghanita Laski on IMDb
- "Two portraits of Laski". National Portrait Gallery.