In folklore and literature, the Fairy Queen or Queen of the Fairies is a female ruler of the fairies, sometimes but not always paired with a king. Depending on the work, she may be named or unnamed; Titania and Mab are two frequently used names. Numerous characters, goddesses or folkloric spirits worldwide have been labeled as Fairy Queens.

Queen Mab is a fairy referred to in William Shakespeare's play Romeo and Juliet, where "she is the fairies' midwife". Later, she appears in other poetry and literature, and in various guises in drama and cinema. In the play, her activity is described in a famous speech by Mercutio published originally in prose and often adapted into iambic pentameter, in which she is a miniature creature who performs midnight pranks upon sleepers. Being driven by a team of atomies, she rides her chariot over their noses and "delivers the fancies of sleeping men". She is also described as a midwife to help sleepers "give birth" to their dreams. Later depictions have typically portrayed her as the Queen of the Fairies.