BDA Sports Management confirmed the signing late Tuesday on Instagram.
Fall, 25, entered the league with the Celtics in 2019 as an undrafted free agent. The 7-foot-5 center averaged 3.3 points and 2.0 rebounds per game in seven appearances in his first season.
He posted 2.5 points and 2.7 rebounds per game in 19 appearances last season.
Fall's contract with the Cavaliers is not guaranteed. He is expected to compete for a roster spot or join the team on a two-way contract.
The Cavaliers roster also features 7-foot centers Lauri Markkanen and Evan Mobley and 6-foot-11 center Jarrett Allen.
The Cavaliers start their preseason schedule against the Chicago Bulls at 8 p.m. EDT Oct. 5 at the United Center in Chicago.