He said: "Xabi Alonso or Aquilani? You also have to consider the age. The Roma player is young so he could become the best midfielder in Europe and even in the world.
"He helped Roma play the best football of the year - they gave a footballing lesson to everyone with a backbone of Italian players."
However, Buffon does not think it is likely Aquilani - a lifelong Roma fan - will leave his hometown club to move to Turin.
But the Juve star hinted at other big moves in the transfer market for the Bianconeri.
"I don't think Roma will let go of a player who is so young and so strong," added Buffon.
"Juventus are planning to buy many players - at the level of the great expectations of all the Bianconeri fans. I don't know if it will be enormous, but it certainly will not let the fans' hopes down."