Jovetic admitted earlier in the week that a move to Arsenal could tempt him to leave Italy but Toni believes the North London club are no bigger than the side he currently plays for.
Toni wants his team-mate to stay put but says if he leaves it should be for the likes of Manchester United, Manchester City or Chelsea.
The former Bayern Munich striker said: "I tell him to think carefully before leaving Florence, as there is an important project here.
"If he has to leave, then make it for a real top club. Chelsea, Manchester City and Manchester United fit that bill, but Arsenal are not better than Fiorentina."
Jovetic has been in good form this season and is part of a Fiorentina side that is battling for a UEFA Champions League place in Serie A.