Oates was born in New York state, the daughter of a tool-and-die designer. She studied English at Syracuse University (B.A., 1960) and the University of Wisconsin (M.A., 1961). She taught English at the University of Detroit, in Michigan, from 1961 to 1967 and at the University of Windsor, in Ontario, Canada, from 1967 to 1978. From 1978 she taught at Princeton University. In 1961 she married Raymond J. Smith, a fellow English student who himself became a professor and an editor. With him she published The Ontario Review, a literary magazine.

Early in her career Oates contributed short stories to a number of magazines and reviews, including the Prairie Schooner, Literary Review, Southwest Review, and Epoch, and in 1963 published her first collection of short stories, By the North Gate. Her first novel, With Shuddering Fall, appeared in 1964 and was followed by a second short-story collection, Upon the Sweeping Flood (1965). She wrote prolifically thereafter, averaging about two books per year.

Her notable fiction works include A Garden of Earthly Delights (1967), them (1969; winner of a National Book Award), Do with Me What You Will (1973), Black Water (1992), Foxfire: Confessions of a Girl Gang (1993), Zombie (1995), We Were the Mulvaneys (1996), Broke Heart Blues (1999), The Falls (2004), and My Sister, My Love: The Intimate Story of Skyler Rampike (2008). In 2001 she published the short-story collection Faithless: Tales of Transgression, “richly various” tales of sin. An extensive and mainly retrospective volume of her stories, High Lonesome: New & Selected Stories, 1966–2006, was published in 2006. The story collection Wild Nights!: Stories About the Last Days of Poe, Dickinson, Twain, James, and Hemingway (2008) featured fictionalized accounts of the final days of various iconic American writers. Oates also wrote mysteries (under the pseudonyms Rosamond Smith and Lauren Kelly), plays, essays, poetry, and literary criticism. Essays, reviews, and other prose pieces are included in Where I've Been, and Where I'm Going (1999).

Oates's novels encompass a variety of historical settings and literary genres. She typically portrays American individuals whose intensely experienced and obsessive lives end in bloodshed and self-destruction owing to larger forces beyond their control. Her books blend a realistic treatment of everyday life with horrific and even sensational depictions of violence.