Bertrand joined Villa on loan during the January transfer window and the left-back has impressed during his short time at Villa Park.
Reports have suggested that Villa boss Paul Lambert is keen to make the move permanent, but Mourinho has cooled talk of Bertrand leaving Chelsea on a full-time basis, suggesting the 24-year-old could have a future at Stamford Bridge.
"He has a future at Chelsea," said Mourinho. "A future and a past. Of course he has a future.
"The decision to let him go to Villa was good because he's playing and what he needed was to play every game.
"But maybe next season he is with us."
Villa will be unable to call upon Bertrand this weekend as he is ineligible to face his parent club Chelsea, in a game which is live on Sky Sports 1HD on Saturday at 5.30pm.