She grew up as an only child in Glasgow, and when young began drawing and writing stories. She started writing children's books in 1976, and attended art school in Edinburgh from 1979 to 1984. She then received a travelling scholarship award to go to Milan, and worked as a freelance from 1984 onwards Bloomsbury.com - Children's Authors.
She is the author/illustrator of many books for children including Mr Bear, the winner of a Children's Book Award. She is best known for her black comedy Pure Dead series for older children, which display strong elements of family lives amid dark and fantasy-based plots.
Debi Gliori has written and illustrated numerous picture books. Pure Dead Magic was her first novel. She has at least five children, one golden retriever, and a colony of sea monkeys.