The Greenwich Hospital is a Crown Charity that cares for the retired seamen and the relatives of those who are wounded or killed at sea while in the service of Britain's navy. It was the idea of Queen Mary II (ruled 1688 - 1693), and was originally planned to be the naval equivalent of the Chelsea Hospital for soldiers. Although Mary died before the charity could be founded, her husband King William III followed up on Mary's wishes and Greenwich Hospital was created by Royal Charter in 1694.

The Hospital buildings were designed by Sir Christopher Wren, the great architect who designed most of London following the Great Fire of 1666, including St. Paul's Cathedral. Building began in 1696 on land adjacent to the Royal Palace at Greenwich, next to the river Thames. Work was completed by 1705, when the first pensioners were admitted. At the same time the Hospital provided for widows and orphans of Britain's seafarers, sailors and marines. A school for the orphans was also set up at this time and housed in the new buildings.

The Hospital remained until 1869, when pensioners were no longer housed in the palace, and in 1873 the buildings were taken over by the Royal Naval College. The school remained until 1933, however, when it moved to Holbrook in Suffolk, and continued to be administered by Greenwich Hospital. The buildings are now a major tourist attraction, especially the Painted Hall, and the National Maritime Museum is also located there.

Today Greenwich Hospital still owns the Royal Hospital School and continues to subsidise fees for pupils with naval connections. The charity also pays out pensions to retired seafarers, its original purpose. The Greenwich Foundation is now responsible for the palace buildings, as the navy left the premises in 1998 (although the naval college moved to Dartmouth in 1905). Greenwich Hospital is led by a Director, appointed by the Charity itself. The current Director is Rear Admiral John Chadwick CB, who was appointed in early March 2003.