Gomez was shown a straight red card for serious foul play just two minutes into the second half on Saturday after a lunge at defender Danny Rose.
The Spaniard was set to miss out in the Latics' three fixtures this month as a result but a regulatory commission upheld Gomez's claim for wrongful dismissal, the Football Association confirmed on Tuesday.
He will therefore be available for Wigan's home clash against Everton at the weekend - news which was welcomed by Roberto Martinez.
"It does not bring back the time lost when Jordi had to leave the field but I am delighted that we can draw a line under this incident and that Jordi is available for us on Saturday," said the Wigan boss on the club's official website.
The Latics had enjoyed the better of the opening 45 minutes at the Stadium of Light but Gomez's sending off changed the game and Steven Fletcher fired Sunderland to their first Premier League victory of the season.