The 26-year-old will join the GUINNESS PRO12 side in the summer and has put pen-to-paper on a deal at Scotstoun until May 2017.
Favaro, who has 23 caps for Italy, has played 35 times for Benetton Treviso and has represented Aironi on 30 occasions. Prior to that he played for Rugby Rovigo and Crociati RFC in the Italian Super 10 league.
At the age of 20 he became the youngest player to be named in Nick Mallett's Italy squad for the 2009 RBS 6 Nations, before going on to make his debut against Australia on the summer tour that year.
Favaro scored his first try for his country in a 24-13 win over Samoa last November and is in the Italy squad for the RBS 6 Nations, with Scotland set to play Italy at BT Murrayfield on Saturday 28 February.
Simone Favaro said: "I'm very excited about this opportunity to play overseas. I've played in Italy all of my career, so this is a new challenge for me.
"Glasgow Warriors are one of the top sides in the GUINNESS PRO12 and have performed well in Europe this season.
"I believe I can become an even better player working with the coaches in Glasgow and I'm looking forward to continuing my development in Scotland when I move there in the summer.
"At the moment my focus is on playing for my country in the RBS 6 Nations and then helping Benetton Treviso finish as high up the league as possible."
Glasgow Warriors head coach Gregor Townsend added: "Simone is an excellent signing for the club and he'll add more depth and competition for places in the back-row.
"He is a very committed player who tackles low and competes hard for ball in contact.
"Simone has played regularly in the GUINNESS PRO12 and in Europe and has more than 20 caps for his country, so he'll bring a lot of experience when he joins us in the summer.
"I believe he will develop further within our environment and with the ability of playing at either 6 or 7, he's going to increase our options in the back-row."
Guinness PRO12
Suite 208, Alexandra House,
The Sweepstakes
Ballsbridge, Dublin 4, Ireland