Parsifal (WWV 111) is an opera in three acts by German composer Richard Wagner. It is loosely based on Parzival by Wolfram von Eschenbach, a 13th-century epic poem of the Arthurian knight Parzival (Percival) and his quest for the Holy Grail (12th century).

Wagner conceived the work in April 1857, but did not finish it until 25 years later. It was his last completed opera, and in composing it he took advantage of the particular acoustics of his Bayreuth Festspielhaus. Parsifal was first produced at the second Bayreuth Festival in 1882. The Bayreuth Festival maintained a monopoly on Parsifal productions until 1903, when the opera was performed at the Metropolitan Opera in New York.

Wagner described Parsifal not as an opera, but as Ein Bühnenweihfestspiel ("A Festival Play for the Consecration of the Stage"). At Bayreuth a tradition has arisen that audiences do not applaud at the end of the first act.

Wagner's spelling of Parsifal instead of the Parzival that he had used up to 1877 is informed by one of the theories about the name Percival, according to which it is of Arabic origin, Parsi (or Parseh) Fal meaning "pure (or poor) fool".