A pourquoi story (French pronunciation: [puʁ.kwa] ^ⓘ; "pourquoi" meaning "why" in French) is a fictional narrative that explains why something is the way it is, for example why snakes have no legs or why tigers have striped coats. Many legends, origin myths and folk tales are pourquoi stories. A more pejorative term for these stories is a just-so story, coined by English writer Rudyard Kipling in 1902.

Pourquoi stories include: