Guardiola won 14 titles - including two Champions Leagues - while coach of the Catalan giants, but Bartomeu promised the club remained focused ahead of their Champions League semi.
"Sooner or later Guardiola will return to Barca," Bartomeu told TV3. "Why will we not do anything special on his return?
"They (Bayern) are coming here to progress from this tie and, although he did a spectacular job when he was at Barca, we cannot get distracted.
"Once the game is over, I'm sure we will see each other in the changing rooms."