The Germany international is back in training after nearly five months out of action but will not feature at the Artemio Franchi.
The Germany international has been sidelined since September with a knee injury but was given the green light to resume training this week, prompting speculation that the forward could feature against Atalanta on Saturday.
However, Montella explained on the eve of the game at the Artemio Franchi that he is unwilling to take any risks with Gomez.
"He is training only gradually, avoiding tackles, so to call him up just to experience being on the field again seems premature to me," the Viola coach told reporters. "We'll see in a few days, though."
Montella is instead hoping that on-loan AC Milan striker Alessandro Matri can fill the void left by Gomez and Fiorentina's other key injury absentee, Giuseppe Rossi.
"[Matri] is very important for us," he acknowledged. "But we need to give him more service because we know that he knows how to do damage in the penalty area."
Matri netted twice on his Fiorentina debut on Jan. 19, at Catania, but has not scored in the interim.