The striker was suspended after biting Italy's Giorgio Chiellini during a World Cup group game, which Uruguay went on to win 1-0.
However, the player had been hopeful Fifa would show leniency, having apologised to Chiellini through social media.
Fifa has remained unmoved, though, and has upheld the sanctions, though he will be able to undergo a medical ahead of his soon-to-be-completed £70m move to Barcelona from Liverpool.
A Fifa statement confirmed: "The Fifa Appeal Committee has decided to reject the appeals lodged by both the Uruguayan player Luis Suárez and the Uruguayan FA, and to confirm the decision rendered by the FIFA Disciplinary Committee on 25 June 2014 in its entirety.
"The terms of the decision taken by the Fifa Appeal Committee were communicated to the player and the Uruguayan FA today."
The decision is not yet final and Suarez or the Uruguayan FA could yet lodge an appeal with the Court of Arbitration of Sport, according to Fifa.