For the mythological creature, see boggart.

A boggart in the Harry Potter fictional books is a shape-shifter that takes on the form of its intended victim's worst fear. It generally likes to hide in dark, enclosed places, such as in closets, under beds, or in hollow trees.

In Harry Potter and the Prisoner of Azkaban, Professor Lupin teaches his students in Defence Against the Dark Arts to approach a boggart in groups of two or more, so that the boggart will have difficulty in choosing which one to frighten and also so that if one target is frightened, the others will be less so since they will likely have different fears. A common wizards' defence against a boggart is to use a spell to make it appear amusing, since boggarts are weakened by laughter. This is achieved by pointing a wand at the boggart and saying "Riddikulus"; this charm can apparently also be used to destroy an already weakened boggart. Lupin later uses a boggart to teach Harry to fight Dementors, as they are Harry's greatest fear.

In Harry Potter and the Order of the Phoenix, a boggart is hidden in a drawer in Number 12 Grimmauld Place. When Mrs. Weasley tries to get rid of the boggart, Harry sees the boggart imitating the dead bodies of the Weasley family and Harry himself. Mrs. Weasley is so terrified by this that she has a nervous breakdown and has to be rescued by her companions.

Characters and their boggarts

• Harry Potter - A Dementor
• Ron Weasley - an Acromantula
• Hermione Granger - McGonagall telling her she had failed everything
• Neville Longbottom - Professor Snape
• Remus Lupin - The moon
• Molly Weasley - Those whom she cares about dead
• Parvati Patil - A mummy
• Seamus Finnigan - A banshee
• Dean Thomas - A hand walking on its own

Note: It is possible that many of these people's boggarts have changed. For example, with the Death Eater who destroyed his parents' sanity on the loose, Neville's greatest fear may have become Bellatrix Lestrange. Also, Hermione encountered her boggart during an exam, so that may account for it taking the form of Professor McGonagall.