Mary Howitt (12 March 1799 – 30 January 1888) was an English writer, editor, translator and a pioneer of the women's rights movement in the UK. She is most known as the author of the famous poem The Spider and the Fly. She translated several works by Hans Christian Andersen and Frederika Bremer. Some of her works were written in conjunction with her husband, William Howitt. Many, in verse and prose, were intended for young people.

Mary Botham, daughter of Samuel Botham and Ann, was born at Coleford, Gloucestershire, where her parents lived temporarily, while her father, a prosperous Quaker surveyor and former farmer of Uttoxeter, Staffordshire, looked after some mining property. In 1796, aged 38, Samuel had married 32-year-old Ann, daughter of a Shrewsbury ribbon-weaver. They had four children: Anna, Mary, Emma and Charles. Their Queen Anne house is now called Howitt Place. Mary Botham was taught at home, read widely and began writing verse at a very early age.

On 16 April 1821 she married William Howitt and began a career of joint authorship with him. Her life was bound up with that of her husband; she was separated from him only during a period when he journeyed to Australia (1851–1854). She and her husband wrote over 180 books.

The Howitts lived initially in Heanor in Derbyshire, where William was a pharmacist. Not until 1823, when they were living in Nottingham, did William decide to give up his business with his brother Richard and concentrate with Mary on writing. Their literary productions at first consisted mainly of poetry and other contributions to annuals and periodicals. A selection appeared in 1827 as The Desolation of Eyam and other Poems.

The couple mixed with many literary figures, including Charles Dickens, Elizabeth Gaskell and Elizabeth Barrett Browning. On moving to Esher in 1837, Howitt began writing a long series of well-known tales for children, with signal success. In 1837 they toured Northern England and stayed with William and Dorothy Wordsworth. Their work was generally well regarded: in 1839 Queen Victoria gave George Byng a copy of Mary's Hymns and Fireside Verses.

William and Mary moved to London in 1843, and after a second move in 1844, counted Tennyson amongst their neighbours. While William was in Australia, Mary was responsible for getting his collection Stories from English and Foreign Life, a translation Ennemoser's History of Magic, and the Australian Boy's Book, through the press. During this time she also compiled a history of the United States and edited and wrote various juvenile works. Her Popular History of the United States, published in the United Kingdom in 1859 and the United States in 1860, was "quickly forgotten" in its time but has been praised in the 21st century as a "well-crafted work" that "surpassed all previous histories in its fluid literary style." Uniquely, she paid full attention to slavery, including its role in the north, and made "unprecedented criticisms" of slave codes in New York and South Carolina, compared the "so-called 1741 New York slave revolt" to the Salem witch trials, condemned the American Colonization Society, and pointed out the hypocrisy underlying the American Revolution, in which colonists contended for "their own liberty" while "depriving other people of theirs."

In 1853 they moved to West Hill in Highgate close to Hillside, the home of their friends, the physician and sanitary reformer Thomas Southwood Smith and his partner, the artist Margaret and her sister Mary Gillies. Mary Howitt had some years earlier arranged that the children's writer Hans Christian Andersen would visit Hillside to see the haymaking during his trip to England in 1847. After 1856 Mary, besides anonymous contributions to periodical literature of the day, edited with the assistance of her daughter A Treasury of Stories for the Young, in three volumes.

Mary Howitt strongly supported the advancement of women's rights as a professional writer, an editor, translator, mother and campaigner. Her periodical Howitt's Journal (1847–1848), co-edited with her husband, contained a progressive political agenda that allowed women to engage in debates on social and political issues. She translated the works of the Swedish novelist Fredrika Bremer who also championed women's rights. As a mother she gave her two daughters, Anna Mary Howitt and Margaret Howitt, every opportunity to develop their professional careers. In a letter addressed to her sister Anna she insisted that 'Girls must be made independent.' Through her eldest daughter Anna Mary and her good friend Barbara Leigh Smith Bodichon, author of the pamphlet A Brief Summary of the Laws of England Concerning Women (1854), she became involved as secretary of the Married Women's Property Committee (MWPC). This committee included other eminent and established professional women writers and Leigh Smith's friends such as Anna Mary, Bessie Rayner Parkes and Eliza Bridell Fox. Leigh Smith drafted a petition, which was circulated nationally, with a request for signatures to support a Married Women's Property Bill. Of the 26.000 signatures which were gathered, Mary Howitt personally collected hundreds of signatures. At the head of the petition some respectable married women were placed such as Mary Howitt, Elizabeth Barrett Browning and Elizabeth Gaskell.