The former Everton and Manchester City manager joins the club as football consultant, with Gary Holt and Mark Robson named first-team coaches following relegation to the Sky Bet Championship.
Holt returns to Carrow Road after a year away managing Falkirk in Scotland, while Robson's role is confirmed after he acted as Adams' assistant on an interim basis at the end of the season.
Royle, who spent time at Norwich as a player and led Everton to the FA Cup in 1995, was Adams' manager at Oldham for five years between 1989 and 1994.
"Joe is someone who I have played for at both Championship and Premier League level," Adams said, "and he has amassed a vast amount of knowledge during his time in the game.
"He has been there, seen it and done it so to speak, and has also been very successful during his time as both a player and a manager.
"Mark and Gary are two people I've worked with closely and both will bring enthusiasm, hunger and experience to the coaching team. They have also played at the highest levels in this country."
The Norwich board expects to appoint a new technical director soon, while a director of recruitment is also being sought.