The German champions will be looking to continue their winning start in Group E when they travel to the Stadio Olimpico on Tuesday evening.
"Roma will be a difficult challenge for us," Guardiola told reporters. "Whoever wins does not qualify, as there are still points up for grabs.
"I've always said that this group will be decided at the last hurdle. It will be a great opportunity for us to test our form."
Bayern won their fourth Bundesliga game in a row by claiming a 6-0 win over Werder Bremen at the weekend.