Kouyate was issued with a straight red card by Mark Clattenburg in the 67th minute of West Ham's game against Crystal Palace following a sliding challenge on Palace forward Dwight Gayle.
With Gayle set to face a three match ban, the club decided to appeal for 'wrongful dismissal', and it has since been anounced they have been successful, meaning the player will be available for the game against Arsenal this Saturday.
West Ham will still be annoyed at the decision. The Hammers were leading 2-1 at the time, but after the dismissal conceded a goal, which cost them two crucial points,as they battle for European football next season.