The York Mystery Plays, more properly the York Corpus Christi Plays, are a Middle English cycle of 48 mystery plays or pageants covering sacred history from the creation to the Last Judgment. They were traditionally presented on the feast day of Corpus Christi and were performed in the city of York, from the mid-fourteenth century until their suppression in 1569. The plays are one of four virtually complete surviving English mystery play cycles, along with the Chester Mystery Plays, the Towneley/Wakefield plays and the N-Town plays. Two long, composite, and late mystery pageants have survived from the Coventry cycle and there are records and fragments from other similar productions that took place elsewhere. A manuscript of the plays, probably dating from between 1463 and 1477, is still intact and stored at the British Library.

Mystery plays and miracle plays are among the earliest formally developed plays in medieval Europe. Medieval mystery plays focused on the representation of Bible stories in churches as tableaux with accompanying antiphonal song. They told of subjects such as the Creation, Adam and Eve, the murder of Abel, and the Last Judgment. Often they were performed together in cycles which could last for days. The name derives from mystery used in its sense of miracle, but an occasionally quoted derivation is from ministerium, meaning craft, and so the 'mysteries' or plays performed by the craft guilds.