The highly regarded McDermott will start in the role of Brisbane's football manager this week after 13 years of involvement with the Maroons.
New Queensland Rugby League (QRL) chief executive Ben Ikin was formerly the Broncos' head of football and left the position in May.
Since Ikin's exit, Walters has done a great job to handle coaching the team to the top of the NRL ladder and other duties outside his main role, but McDermott's arrival will take the heat off and provide him with an ally to get the Broncos into a vital top-two position.
The duo are close friends and have an association stretching back to 2012 when Walters was Queensland under 20s coach.
McDermott, who was Maroons football manager when Walters was the coach, also held the role of QRL manager of game development and high performance for a decade.
"Joe has great experience across all levels of the game and all situations and will be a great asset to us," Walters told AAP.
"He has a very strong character and is very calm in pressure situations. He has had to deal with all of that in State of Origin deciders and Origin games all over Australia.
"Joe has worked with great players and coaches including Mal Meninga, Paul Green, Wayne Bennett and now Billy Slater.
"He has thrived in those pressure-cooker scenarios at Origin level which is going to be a big help to us."
"He is very humble and has no ego at all.
"That is a great trait to have at a big club like ours with lots of personalities, so he will fit in nicely."
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