Eucharistic miracle of Lanciano

The Miracle of Lanciano is a Eucharistic miracle said to have occurred in the eighth century in the city of Lanciano, Italy. According to tradition, a Basilian monk who had doubts about the real presence of Christ in the Eucharist found, when he said the words of consecration at Mass, that the bread and wine changed into flesh and blood. The Catholic Church officially recognizes this miracle as authentic. Numerous analyses have been performed on the relic and the historical tradition.

The incident is similar to the tradition known as the Mass of Saint Gregory, first recorded in the 8th century by Paul the Deacon. The Miracle of Lanciano, together with the Eucharistic miracle of Santarém, in Portugal, is considered among the most important of these miracles. The National Catholic Register called it "perhaps the most famous and well-known" of the Eucharistic miracles.

There have been numerous analyses of the miracle claim. Scientific analysis has confirmed the relics kept in Lanciano are heart tissue, though skeptics criticize the historic reliability of the tradition.