The 37 year-old Pole's contract is running down this season and talks over a new deal are yet to commence.
Trezeguet said, "I'd sign Lewandowski for free, even at 37: he's in a league of his own, one of the last nine truly great players alongside (Erling) Haaland.
"Lewandowski might not have the same physique he once did, but despite not playing regularly for Barcelona, he scored 14 goals: he's strong and intelligent. Lewandowski would arrive at Juve knowing where he's come from and what's expected of him: goals. If I had the chance, I'd bring him to Turin myself."
The Frenchman also recalled: "(Luciano) Moggi (ex-director general) was tempted to sell me to Barcelona. (Fabio) Capello was the deciding factor. Fabio called me and asked me to stay, but he was still at Roma at the time...
"To be honest, I didn't have much faith, but in the end it worked out. We had a great team and I thought it would be easier to win the Champions League with Juventus. Instead, in 2006, Barça triumphed..."