Bale became the world's most expensive player when he signed for Real Madrid for a reported £86m at the end of August, but the Gunners boss feels that the Welshman is not yet on the same level as Ronaldo and Messi.
"Bale still has a way to go if you compare what Ronaldo has done and what Bale has done," Wenger told ITV Sport.
"[Ronaldo] is a complete athlete with total efficiency and Messi is an artist who does things nobody else can do.
"Bale has still a way to make it but the vision of having [Ronaldo and Bale] together is very exciting."
The former Tottenham Hotspur winger has been ruled out of tonight's visit of Copenhagen in the Champions League.