The Spain midfielder secured a long-awaited move back to his boyhood club in August 2011 after spending eight seasons with the north Londoners.
Wenger believes the 25-year-old midfielder, who has scored six goals in all competitions for Barça this term, could return to the Premier League club in the next few years.
“I’m not convinced Fàbregas won’t come back here one day,” said Wenger. “He’s an Arsenal man. He loves Arsenal. He watches every Arsenal game.
“Barcelona was his home town where he grew up and you have to accept this, especially as Barcelona are the best team in the world.
“He won’t return in the next two or three years but, after that, maybe.”
Fàbregas scored 57 goals and made 100 assists in 303 appearances during his eight-year spell in north London.
Arsenal take on defending Premier League champions Manchester City at Emirates Stadium on Sunday.
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