Ubu Roi ([yby wa]; "Ubu the King" or "King Ubu") is a play by French writer Alfred Jarry, then 23 years old. It was first performed in Paris in 1896, by Aurlien Lugn-Poe's Thtre de l'uvre at the Nouveau-Thtre (today, the Thtre de Paris). The production's single public performance baffled and offended audiences with its unruliness and obscenity. Considered to be a wild, bizarre and comic play, significant for the way it overturns cultural rules, norms and conventions, it is seen by 20th- and 21st-century scholars to have opened the door for what became known as modernism in the 20th century, and as a precursor to Dadaism, Surrealism and the Theatre of the Absurd.

Alfred Jarry (French: [al.fʁɛd ʒa.ʁi]; 8 September 1873 – 1 November 1907) was a French symbolist writer who is best known for his play Ubu Roi (1896). He also coined the term and philosophical concept of 'pataphysics.Jarry was born in Laval, Mayenne, France, and his mother was from Brittany. He was associated with the Symbolist movement. His play Ubu Roi is often cited as a forerunner of Dada and the Surrealist and Futurist movements of the 1920s and 1930s. He wrote in a variety of hybrid genres and styles, prefiguring the postmodern, including novels, poems, short plays and opéras bouffes, absurdist essays and speculative journalism. His texts are considered examples of absurdist literature and postmodern philosophy.