Bower will join a Suns team that has the second-worst record in the NBA at 19-63.
Bower last served as general manager of the Detroit Pistons from 2014 to 2018. Before that he was with the New Orleans Hornets, as general manager for two stints from 2002 to 2003 and 2005 to 2010.
He also was the head coach for the Hornets for 73 games during the 2009-2010 season. Bower coached at Marist college for the 2013-14 season.
Bower will take over a Suns team that has missed the postseason for nine straight seasons.