Childress, 34, last played in the NBA during the 2013-14 season with New Orleans. He was co-captain of the Ball Hogs team that participated in the inaugural season of the Big3 league, founded by Ice Cube.
Though Childress has signed with Denver, it's unlikely he'll make the Nuggets' roster, sources told ESPN.
Basketball Insiders was first to report that Childress signed with Denver.
He averaged 9.1 points and 4.7 rebounds in 391 career games in the NBA.