The Chilean forward was benched for Saturday's 3-1 defeat to Liverpool but returns in European competitions, while Mesut Ozil is only fit enough to start as a substitute.
Wenger's decision to start Sanchez on the bench against Liverpool was an unpopular one and the French coach came in for plenty of criticism following his side's heavy defeat.
He will be hoping that the former Barcelona attacker can make an immediate impact on his return to the team as the Gunners attempt to beat the odds and overturn a 5-1 defeat from the first leg.
Sanchez's cause will be aided by the presence of Olivier Giroud alongside him, with the Frenchman drafted into the team after Danny Welbeck picked up a knock in the warm-up.
Meanwhile, Carlo Ancelotti has named a formidable starting team, despite boasting a strong advantage over the Premier League outfit.
Arjen Robben is joined in attack by Franck Ribery and Robert Lewandowski as the Bavarians look to close out the tie, but Thomas Muller is confined to the bench.
Arsenal XI: Ospina; Mustafi, Koscielny, Monreal, Bellerin; Ramsey, Xhaka, Oxlade-Chamberlain; Walcott, Alexis, Giroud
Subs: Cech, Gibbs, Gabriel, Coquelin, Ozil, Lucas
Bayern Munich XI: Neuer; Hummels, Martinez, Rafinha, Alaba; Thiago, Alonso, Vidal; Ribery, Robben, Lewandowski
Subs: Ulreich, Costa, Bernat, Muller, Coman, Kimmich, Sanches