Son of a Witch (2005) is a fantasy novel by American writer Gregory Maguire. The book is Maguire’s fifth revisionist story and the second set in the land of Oz originally conceived by L. Frank Baum. Son of a Witch continues the story after the fall from power of the Wizard of Oz and the death of Elphaba by recounting the life of Elphaba’s son, Liir. The book is dedicated to the cast of the Broadway musical version of Wicked.

Gregory Maguire is an American novelist. He is the author of Wicked, Confessions of an Ugly Stepsister, and several dozen other novels for adults and children. Many of Maguire's adult novels are inspired by classic children's stories. Maguire published his first novel, The Lightning Time, in 1978. Wicked, published in 1995, was his first novel for adults. It was adapted into a popular Broadway musical in 2003.