It will be the first time the engineering giant has made engines for the Gulf carrier?s super-jumbo fleet.
The news boosted Rolls-Royce?s share price after a year of profit warnings.
Emirates said the deal gave further support to trade ties between the UK and the United Arab Emirates and would have a ?significant economic impact?.
Announcing the deal in London, Emirates president Sir Tim Clark said: ?Today?s announcement is significant not only because it cements the partnership between Emirates and Rolls-Royce, but also because of the significant economic impact that this will have on aviation manufacturing in the UK and Europe.?
BBC