My Father's Dragon is a 1948 children's novel by Ruth Stiles Gannett, with illustrations by her stepmother Ruth Chrisman Gannett. The novel is about a young boy, Elmer, who runs away to Wild Island to rescue a baby dragon.
Both a Newbery Honor Book and an ALA Notable Book, it is the first book of a trilogy whose other titles are Elmer and the Dragon and The Dragons of Blueland. All three were published in a 50-year anniversary edition as Three Tales of My Father's Dragon (summary by Wikipedia)