Cavaliers general manager Kobe Altman made the announcement Nwaba would be joining on Saturday.
The 25-year-old had been in discussions with several other organisations, including the Chicago Bulls and Indiana Pacers, before reaching a one-year agreement with Cleveland.
Nwaba averaged 7.9 points and 4.7 rebounds in 23.5 minutes per game across 70 appearances (21 starts) last season with the Bulls, who claimed him off waivers inJuly 2017.
He was a restricted free agent, but Nwaba’s $1.7million qualifying offer was pulled by the Bulls during the summer, which made him an unrestricted free agent.
The 6ft 4in guard out of Cal Poly went undrafted in the 2016 NBA Draft and then spent the 2016/17 campaign with the Los Angeles Lakers.
There he averaged 6.0 points and 3.2 rebounds in 20 games – two starts – while moving back and forth between the Lakers and their G League affiliate.
Nwaba will likely join the Cavaliers’ rotation system and give coach Tyronn Lue added depth as he looks to stay competitive following the departure of LeBron James to the Los Angeles Lakers in the summer.
Nwaba is expected to wear the number 12 jersey for the Cavaliers.