The royal wedding of Mary I and Philip II of Spain celebrated at Winchester Cathedral.

Mary I of England (1516–1558) and Philip of Spain married at Winchester Cathedral on Wednesday 25 July 1554.

Mary I, also known as Mary Tudor, was Queen of England and Ireland from July 1553 and Queen of Spain as the wife of King Philip II from January 1556 until her death in 1558. She made vigorous attempts to reverse the English Reformation, which had begun during the reign of her father, King Henry VIII. Her attempt to restore to the Church the property confiscated in the previous two reigns was largely thwarted by Parliament but, during her five-year reign, more than 280 religious dissenters were burned at the stake in what became known as the Marian persecutions, leading later commentators to label her "Bloody Mary".

Philip II, sometimes known in Spain as Philip the Prudent, was King of Spain from 1556, King of Portugal from 1580, and King of Naples and Sicily from 1554 until his death in 1598. He was also jure uxoris King of England and Ireland from his marriage to Queen Mary I in 1554 until her death in 1558. Further, he was Duke of Milan from 1540. From 1555, he was Lord of the Seventeen Provinces of the Netherlands.

Winchester Cathedral, formally the Cathedral Church of the Holy Trinity and of Saint Peter and Saint Paul and of Saint Swithun in Winchester, is the cathedral of the city of Winchester, England, and is among the largest of its kind in Northern Europe. The cathedral is the seat of the Bishop of Winchester and is the mother church for the ancient Diocese of Winchester. It is run by a dean and chapter, under the Dean of Winchester.