The monarch was the first to lay a wreath at the Cenotaph to commemorate those servicemen and women killed in all conflicts since the First World War.
The Prime Minister David Cameron also attended the service along with Armed Forces Minister Nick Harvey, Chiefs of Staff, Deputy Prime Minister Nick Clegg and opposition leader Ed Miliband.
About 4,500 ex- and current Service personnel took part in a march past the Cenotaph.
The Queen stood metres from the Cenotaph, eyes fixed on the memorial, while behind the sovereign stood members of the Royal Family including the Duke of Edinburgh, the Prince of Wales, the Duke of York, the Earl of Wessex, the Princess Royal and the Duke of Kent.
Soldiers from the King’s Troop Royal Horse Artillery fired a round from nearby Horse Guards Parade which echoed around Whitehall to signal the end of the two minutes’ silence.
As the artillery blast faded buglers of the Royal Marines sounded the haunting melody of the Last Post, which traditionally signalled the end of a soldier’s day.
The Bishop of London, Richard Chartres, led the short service at the Cenotaph where prayers were said for those ‘who have died in service of their country and the Crown’.
The march past by old soldiers was led by the British Korean Veterans Association proudly wearing their regimental berets and medals.
They were followed by dozens of organisations representing servicemen from past conflicts.
Stuart Gendall from the Royal British Legion said:
Every year at this time we take time out for silent reflection on the sacrifices that have been made on our behalf and hope for a more peaceful future.
Today we’re still in a conflict and seeing more people make the ultimate sacrifice.
But it brings us together, it’s non-political, all faiths are here and it allows us to remember those who have gone as human beings.
Remembrance Sunday services also took place today in Afghanistan where at Camp Bastion Prince William and Defence Secretary Dr Liam Fox made a surprise visit - see Related News.
The British Legion has made the theme of this year’s Poppy Appeal the ‘Afghan generation’ of the Armed Forces and their families. A British Legion spokesman said demand for poppies had been so great that it had had to dip into next year’s supply.
Elsewhere across the UK, HMS Ark Royal crew members led a parade as part of Glasgow’s ceremony in George Square, and a service was held in Glasgow Cathedral. A ceremony was also held at the Stone of Remembrance on Edinburgh’s Royal Mile.
In Belfast, tributes at the City Hall were led by the Lord Mayor, while in Cardiff a march by armed forces and veterans organisations was followed by a service at the Welsh National War Memorial in Cathays Park.