The Turkish champions will qualify for the last 16 should they defeat Juve at the Turk Telekom Arena on Tuesday.
Attacking midfielder Sneijder has struggled with a recurring thigh injury in recent times and has featured just once - as a substitute - since November 1.
However, Galatasaray coach Mancini is set to be boosted by the return of the former Inter man as the hosts look to reach the knockout stage for the second consecutive season.
"We will finally look at Wesley Sneijder's situation tomorrow (Tuesday) morning," Mancini said.
"He feels good and it seems that there will be no obstacle to play."
Former Manchester City boss Mancini is confident his club can beat the Serie A title-holders and secure qualification.
"Our primary goal is not conceding. If we do not allow our rivals to find chances, I think we will win this game," he added.
"Our target is definitely qualifying for the next round. We are not thinking of another possibility, such as finishing the group in third place."
