The goalkeeper officially joins the Gunners for the remainder of the season from Palermo after passing a medical at their London Colney training ground on Monday morning
The Italian passed a medical at the Gunners' London Colney training ground on Monday morning and agreed terms to spend a year at the Emirates Stadium.
Viviano, whom Arsenal have an option to buy at the end of the campaign, will provide competition for current No.1 Wojciech Szczesny.
It is understood that the north Londoners had to pay a substantial loan fee for the keeper, who spent 2012-13 with Fiorentina in a similar temporary deal.
Palermo announced the deal on their official website, confirming that Arsenal have taken the Italian on loan for the season with the right to buy him outright.
The Gunners are also soon to announce the €47 million arrival of Real Madrid playmaker Mesut Ozil, with a five-year contract agreed on Monday.
Arsene Wenger also wants to take Chelsea striker Demba Ba on loan for the season but the Blues are demanding a €2.3m fee if they are to let their man go to the Emirates Stadium.