Morris, whose friendship with head coach Gus Malzahn traces back some two decades, replaces Kenny Dillingham, who left for the same position at Florida State.
"I'm super excited to have Chad Morris join our staff at Auburn," Malzahn said in a statement. "He's a tremendous offensive mind who has had success with several top-ranked offenses during his time in the college ranks. I've known Chad for almost 20 years and he is a tireless worker and a perfectionist."
At Auburn, Morris will work closely with starting quarterback Bo Nix, who has started every game as a true freshman this season, leading the Tigers to a 9-3 record while passing for 15 touchdowns and six interceptions.
Morris' son, Chandler, who is an ESPN 300 QB, decommitted from Arkansas when his father was fired. Auburn was one of his first offers when his recruitment began.
Auburn will play Minnesota in the Outback Bowl on Jan. 1.