Sport Mediaset claim that the Naples-based side offered to take the Belgian to San Paolo on a temporary deal, but failed.
The Belgium international has shown over the years at White Hart Lane that he is a supremely gifted footballer but has failed to show the consistency to win over the entire Spurs faithful.
Dembele has also not yet found a role at the North London club to call his own, with Mauricio Pochettino experimenting with the former Fulham man on the right flank this term in an interesting ploy.
It is clear that the Belgian playmaker is in the Argentine trainer’s plans, given that he has started all four Premier League games for Spurs this season so far.
Sport Mediaset claim that Napoli were keen to give Dembele the option of a fresh start in Naples, with a loan offer that included the possibility of the switch becoming permanent on the table.
However, Tottenham are said to have rebuffed the proposal immediately and have vowed to keep the midfielder at White Hart Lane.