Zibby Oneal was born Elizabeth Bisgard to a middle-class family in Omaha, Nebraska. She grew up in a house full of books and says she always knew she wanted to be a writer. She attended Catholic girls' schools and was an English major first at Stanford University, which she attended from 1952 to 1955, then at the University of Michigan, where she finished her bachelor's degree in 1970. In 1955, she married Robert Oneal, a plastic surgeon, with whom she had two children. She taught at the University of Michigan from 1976 to 1985 while writing stories that she told her children. She published her first children's book, War Work, in 1971. She received national recognition in 1980 for The Language of Goldfish, her first young adult novel.