The Partenopei posted a photo of the former Olympique Lyonnais right-back alongside coach Rafa Benitez on their official website on Friday.
Napoli president Aurelio De Laurentiis talked up the wealth of experience and numerous trophies the 33-year-old accumulated during his 10 years at Lyon before parting company with the Ligue 1 club this summer.
"Welcome Anto," the Partenopei supremo wrote on Twitter. "With five championships, seven cups, 77 games in the Champions League and 595 in his career, he can be a great help to us."
Reveillere - who has 20 caps for France, the most recent of which came against Finland in 2012 - is unlikely to feature in Sunday's Serie A clash with Juventus but he will give Benitez an extra defensive option.
Napoli currently sit second in Serie A, behind Roma and level on points with reigning champions Juve.