The Wales full-back begins the suspension after the Football Association charged him following the game against Leeds on Sunday.
Gunter stamped on the foot of Leeds forward Sanchez Watt during the second half of the 1-1 draw at the City Ground.
The incident sparked a melee and both players were handed yellow cards by referee Tony Bates at the time, but the FA have punished Gunter retrospectively.
Long-term injury victim David McGoldrick (shoulder) aside, boss Billy Davies has an otherwise full squad to choose from as Forest look for their first win of the season.
