The Queen had said it was her "sincere wish" that Prince Charles would follow her in the role.
Leaders of the Commonwealth have been discussing the issue at a meeting behind closed doors at Windsor Castle.
The head role is non-hereditary so is not automatically passed on when the Queen dies, with suggestions it might have rotated among the 53 leaders.
'Proud support'
In a statement, the leaders said they "recognise the role of the Queen in championing the Commonwealth and its people".