The federation has penned a two-year deal with Piazza with an option to extend his deal by two more years.
In the meeting, attended by the president of the federation, Milad Taghavi, and members of the media, Piazza expressed his hope of achieving success in the new position.
He will be assisted by his compatriot Tomaso Totolo in Team Melli.
Piazza was named Team Melli coach in early September and traveled to Iran on Monday to finalize his deal.
Piazza has replaced Brazilian coach Mauricio Motta Paes.