He and Adam O’Brien will replace outgoing assistant coaches Kevin Walters and David Kidwell.
Storm Head Coach Craig Bellamy said: “Alex, David and Kevin have been wonderful contributors top this club and I would like to personally thank them for all of their hard work and dedication during their time here at Melbourne Storm.
“With every door that closes another one opens and that is the case with the new appointments. Justin brings wonderful experience from around the world both as a player and coach.”
O’Brien has progressed through Storm’s coaching ranks, having worked through the NYC system and most recently holding the role of development coach for the last two seasons.