The Polish keeper is suffering from an ankle injury, and had only just returned to the Arsenal side in their last game against Southampton after being kept out with a rib injury.
Vito Mannone is expected to take his place, and despite Szczesny making a mistake which allowed Southampton to score in their last game, Gunners boss Arsene Wenger has insisted that he is still first-choice, although did suggest that could change in future:
"Vito is very close, and he gets another opportunity now," said Wenger. "He has belief and he has the mental strength to deal with that."
Wenger also spoke about their French opponents Montpellier, who have lost three of their first five games in Ligue 1. "What they did is a miracle because I think three years ago they were in the second division and one point away from relegation to division three.
"It is difficult to know why they have not started well this season. Maybe because they were champions and now they are the team to beat."