Forni di Sotto () is a (municipality) in the Regional decentralization entity of Udine in the Italian region of Friuli-Venezia Giulia, located about northwest of Trieste and about northwest of Udine. As of 31 December 2004, it had a population of 701 and an area of .
Forni di Sotto borders the following municipalities: Ampezzo, Claut, Forni di Sopra, Sauris, Socchieve, Tramonti di Sopra.