The Uruguay striker was banned for nine international games and told he could not partake in any football activity for four months following the incident - which took place during the World Cup Group D clash against Italy at Estadio das Dunas.
Both Suarez and Uruguayan football's governing body lodged appeals, although they were dismissed by the FIFA Disciplinary Committee on Thursday.
A statement from the organisation read: "The FIFA Appeal Committee has decided to reject the appeals lodged by both the Uruguayan player Luis Suarez 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 relevant decision is not yet final and binding, i.e. an appeal to the Court of Arbitration of Sport (CAS) is still possible (cf. art. 67 par. 1 of the FIFA Statutes) by the player and/or the Uruguayan FA, subject to certain conditions."
It is the third time Suarez has been suspended for biting, the other two coming while on club duty for Ajax and Liverpool respectively.