A minute`s silence will be held during the service and on London`s transport network at 11:30 BST.
Prince William will also attend a service at Hyde Park`s 7 July Memorial.
The attack - by four suicide bombers linked to al-Qaeda and carrying rucksacks of explosives - was the worst single terrorist atrocity on British soil.
At just after 08:50 on 7 July 2005, three explosions took place on the Underground - 26 people died in a bombing at Russell Square on the Piccadilly line; while on the Circle line six died in an explosion at Edgware Road, and seven lost their lives at Aldgate.
Almost an hour later, a fourth device was set off on a number 30 double-decker bus in Tavistock Square, killing 13 people.
The names of the 52 victims will be read out at the national service of commemoration at St Paul`s Cathedral, which begins at 11:00 BST.
More than 700 people were also injured in the attacks.
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