The homeware company has not revealed details of its sponsorship activity, but said it planned to provide "rest and relaxation" for Team GB athletes in the run-up to Rio.
Chief executive Ian Filby said: "At London 2012, Team GB inspired a nation with their commitment, endeavour and excellence. We hope our support can help Team GB reach the same heights at Rio 2016.
"It’s always that little bit harder, that little bit more daunting when you’re competing abroad, but together with Team GB we hope we can make Rio 2016 a home away from home".
Bill Sweeney, chief executive of the British Olympics Assocation, said DFS would aim to recreate the "homely feel" that led to Team GB’s success in the London 2012 competition.
He said: "Brazil is uncharted territory for many of our athletes so as our Official Homeware Partner DFS will play a key role."
A spokeswoman for DFS would not say how much the contract was worth.
Team GB has 10 additional global partners, including Samsung, Coca-Cola, McDonald’s, P&G and Visa.