The Queen is greeted by the Dean of Westminster Abbey, the Reverend John Hall.
The Prince of Wales, Prince William, the Duchess of Cornwall and Prince Harry arrive.
Other royals at the service included Prince Michael and Princess Michael of Kent.
Prime Minister Gordon Brown is all smiles as he arrives at the service accompanied by his wife, Sarah.
Former prime ministers also attended. Baroness Thatcher is sheltered from the rain as she enters Westminster Abbey.
Baroness Thatcher's successor, Sir John Major, is accompanied by his wife, Lady Major.
Other political heavyweights at the service included the first minister of Northern Ireland, Dr Ian Paisley, who was joined by his wife, Eileen.
The Queen and Duke of Edinburgh stand alongside each other during the service to mark their long marriage.
The actress Dame Judi Dench read a poem entitled Diamond Wedding, written by the poet laureate, Andrew Motion, during the service.