The Kawasaki man currently lies fifth in the overall standings with two meetings remaining, 90 points adrift of leader and team-mate Tom Sykes.
NGM Forward Racing announced the news on Saturday, with Baz due to link up with former Moto2 world champion Stefan Bradl for the 2015 campaign.
"It's a pleasure to welcome Loris Baz to our team," commented team owner Giovanni Cuzari.
"He is a young rider who has proved to be fast in World Superbikes and we would like to give him the possibility to show his talent also in MotoGP.
"I'm very happy to start this new adventure with Loris and bring this new rider in the premiere class, continuing our mission of talent scout team alongside Yamaha.
"Loris will partner Stefan Bradl and we are delighted to line up a very young team with a 21-year-old Frenchman and a 24-year-old experienced German rider."