Andre Norton (Alice Mary Norton) was born on February 7, 1912, in Cleveland, Ohio, to Adelbert Freely and Bertha Stemm Norton. Norton began her literary career at an early age, serving as the editor of a literary page in her high school's paper called The Collinwood Spotlight, for which she also wrote short stories. During this time, she actually wrote her first book, Ralestone Luck, which was eventually published as her second novel in 1938.

Norton graduated from high school in 1930, and briefly attended Flora Stone Mather College of Western Reserve University, intending to become a teacher. However, economic circumstances obliged her to leave school in 1932, and instead, she went to work as a librarian with the Cleveland public library system. She was employed here for a number of years, during which time she worked for some time as a children's librarian for the Nottingham Branch Library in Cleveland. After a brief tenure working at the Library of Congress from 1940-1941, and a failed attempt to operate a bookstore in Mount Rainier, MD, she returned to the Cleveland Public Library. Ill health forced her to retire from the library in 1950. From 1950-1958 Norton was a reader at the SF small press Gnome Press.

In 1934, Norton published her first book, the novel The Prince Commands, being sundry adventures of Michael Karl, sometime crown prince & pretender to the throne of Morvania. She changed her name legally to "Andre Norton" at this point, believing that readers of fantasy (at that time a mainly male audience) would accept her more under a pseudonym that was not clearly female. Between 1934 and 1948 she wrote several additional historical novels. Her first genre novel was the historical fantasy Huon of the Horn (1951), an adaptation of the medieval tale of Huon, Duke of Bordeaux. Although her first actual work of science fiction or fantasy was actually the novella "The People of the Crater", which she published under the name "Andrew North" in the 1947 magazine Fantasy Book.

Norton's first science fiction novel was Star Man's Son, 2250 A.D., which was released in 1952. This inaugurated a fertile and prolific creative period in her life. By the end of her life, Norton had produced (or co-written) novels and short stories in over 20 different series (as well as many individual stand-alone works), those series including Beast Master (1959-2006, the first novel of which was semi-adapted into a film in 1982); Central Control (1953-1955); Crosstime (1956-1965); Forerunner (1960-1985); Mark of the Cat (1992-2002); Moon Singer/Moon Magic (1966-1990); Star K'aat (1976-1981); Time Traders (1958-2002); and Trillium (1990-1993).

Norton's most famous creation is probably her Witch World high fantasy novel and story cycle. The first of the series, Witch World, was released by Ace Books in 1963 and tells the story of Simon Tregarth, a resident from our Earth who, fleeing a group of assassins, is transported to a parallel world where magic rules. Magic in the Witch World is the exclusive province of women, a situation that governs much of the events that play out in the series. The novel was nominated for a Hugo Award for Best Novel and sparked a long-running series on which Norton increasingly cooperated with other authors starting in the 1980s. Witch World, then, is an early example of what later became known as a "shared universe."

Andre Norton's abilities were recognized during her lifetime by her peers and her many fans, as evidenced by her many awards and nominations. She was nominated twice for the Hugo Award (in 1963 for Witch World, and in 1968 for Best Novelette ("Wizard's World") for numerous Locus Poll awards, and for several World Fantasy Awards. Her wins include the 1975 Phoenix Award for overall achievement in science fiction, the Gandalf Grand Master of Fantasy Award in 1977 for lifetime achievement, the 1983 Edward E. Smith Award for Imaginative Fiction, the Jules Verne Award in 1984, the 1994 First Fandom Award, and a Life Achievement Award from the World Fantasy Convention in 1998. In 1984 she was made a Grand Master by the Science Fiction Writers of America, the first woman to receive this prestigious award (only three other women since Norton have been given this award).

In addition, she was a founding member in the 1960s of the Swordsmen and Sorcerer's Guild of America (SAGA), a loose-knit group of heroic fantasy authors that granted entry by fantasy credentials alone. Norton was the only woman among the original eight members.

Norton moved from Florida (where she had lived since 1966) to Murfreesboro, TN in 1987. In her later years, one of her more notable projects was the formation of the High Halleck Genre Writer's Research and Reference Library, a special collections library devoted to science fiction, fantasy, and other genre writing, run by Norton on her own property. The library opened in 1999 and was dispersed after Norton's death. She died of congestive heart failure on March 17, 2005. Her last completed novel, Three Hands for Scorpio, was published a few weeks later on April 1.

In 2005, the Science Fiction and Fantasy Writers of America established the Andre Norton Award for Young Adult Science Fiction and Fantasy in Norton's honor. The Norton Award is presented yearly along as part of the Nebula Awards.