Pendragon: Journal of an Adventure through Time and Space, commonly known as The Pendragon Adventure or simply Pendragon, is a series of ten young-adult science fiction and fantasy novels by American author D. J. MacHale, published from 2002 to 2009. The series chronicles the adventures of Bobby Pendragon, an American teenager who discovers that he must travel through time and space to prevent the destruction of the ten "territories": critical times and locations throughout the universe. The series has sold over a million copies.

Each book deals with the battle over a particular territory, fought by Bobby's side against the forces of Saint Dane, a shapeshifting demon, who exploits a decisive turning point for the local people of each territory. At this turning point, Saint Dane steps in to guide the territory towards utter chaos, while Bobby and his allies attempt to stop these efforts.

The novels use a first-person perspective through Bobby's handwritten journal entries, in which he recounts the events of his adventures to his loyal friends back home, Courtney Chetwynde and Mark Dimond, as well as a third-person narrative to tell the stories of characters other than Bobby—often, Courtney and Mark themselves. Each book of the series repeatedly alternates between these two narrative perspectives.