Details of Crawford's life are sketchy. The daughter of a physician who emigrated to Canada in 1858, she spent most of her girlhood in the picturesque Kawartha Lakes district of Ontario. She received an excellent education at home and was widely read in the classics and in French and Italian literature. From 1875 until her death, she and her widowed mother lived in Toronto, meagrely sustained by the sale of her stories and poems to Toronto newspapers and to magazines in the United States.

Required to write to the tastes of her audience, Crawford nonetheless exhibits a wide-ranging knowledge and original vision. Influenced by English Romantic and Victorian writings, Crawford detailed the beauties of the Canadian landscape and the search for ideal love. The only book published during her lifetime (at her own expense) was a paper-covered collection, Old Spookses' Pass, Malcolm's Katie, and Other Poems (1884). It contains outstanding narrative and descriptive passages, marked by vigorous rhythm and bold imagery. It sold only about 50 copies. A later collection of her poems was published in 1905 and reprinted in 1972. Crawford's work was rediscovered in the 1970s. Among the works that have since been published are Selected Stories of Isabella Valancy Crawford (1975), Fairy Tales of Isabella Valancy Crawford (1977), Hugh and Ion (1977; an unfinished narrative poem), The Halton Boys (1979), and Malcolm's Katie: A Love Story (1987).