Wilshere reacted angrily to a late challenge from Matthew Smith, pushing the Manchester City youngster to the floor.
Smith went down as Wilshere became involved in a fiesty scrap with City players.
Tyreke Wilson was also sent off for his role in the melee, with Wilshere looking angry as he walked off the pitch.
Wilshere saw red with Arsenal winning 4-1 with Reiss Nelson and Eddie Nketiah both hitting two goals for the hosts.
Smith kept City in the game but following Wilshere’s dismissal Brahim Diaz and Lukas Nmecha netted.
Wilshere’s red comes on just his second appearance for Arsenal after suffering a fractured leg in April.
The 25-year-old spent last season on loan at Bournemouth but injury put pay to any permanent move.
And Wilshere’s ill-discipline will not have impressed Arsene Wenger as he looks for a way back into the Arsenal first team.
He took exception to Smith’s late challenge in the middle of the pitch, having body-checked the Gunners man to the floor.
Wilshere responded by pushing the City man in the chest, sending him falling to the ground.
The England international then became involved in pushing match with Wilson after the City defender steamed in to confront him.
Referee Samuel Allison dismissed both players, who walked down the tunnel within seconds of each other.
