Which Harry Potter book by J.K. Rowling has the longest title?

Harry Potter and the Order of the Phoenix has the longest title among J.K. Rowling’s seven main Harry Potter books.

The title refers to the Order of the Phoenix, a secret organisation founded by Albus Dumbledore to oppose Lord Voldemort. The group includes adult witches and wizards such as Sirius Black, Remus Lupin, Alastor Moody and members of the Weasley family.

The fifth novel was published in 2003. It follows Harry’s return to Hogwarts after Voldemort’s return and focuses on the Ministry of Magic’s refusal to accept that Voldemort is active again. Dolores Umbridge is installed as Hogwarts’ High Inquisitor and later becomes headmistress, creating direct conflict with Harry and his friends.

The book is also notable for Harry’s growing connection to Voldemort’s mind and for the formation of Dumbledore’s Army. Its film adaptation, released in 2007, starred Daniel Radcliffe as Harry and was directed by David Yates.