At a press conference in Sydney on Friday, Meninga was locked in as the Bears' inaugural coach on a three-year deal.
It is his first foray into club coaching in more than 25 years.
Meninga has renounced his role as coach of the Australian Test team ahead of an end-of-season Ashes tour.
The 64-year-old will now set about building a competitive roster for the Bears' first NRL season in 2027.
"This is one of the most exciting challenges of my career," Meninga said.
"To have the opportunity to take our great game back to Western Australia to start a new team and to bring with it a much-loved rugby league community and heritage brand in the Bears.
"It's a great privilege and responsibility I've been given to be one of the leaders in the formation of the club.
"I'm looking forward getting to stuck into the work that needs to be done to deliver a team that represents WA and is competitive from day one."
Meninga has built a terrific resume working as a representative coach with the Kangaroos, Queensland and Papua New Guinea, but hasn't worked at club level since he left the Canberra Raiders in 2001.
Australian Rugby League Commission boss Peter V'landys AM described Meninga as "the ideal man to lead the game to a new frontier".
"There are very few who have graced our game who can match Mal Meninga's record of success," V'landys said.
"The esteem in which he is held in the sport, his experience and the success he has had at every level of the game as a player and coach will ensure the Perth Bears have exceptionally strong leadership.
Bears chief executive Anthony De Ceglie praised Meninga's leadership, adding he is the "perfect coach to build a brand new team from the ground up".
"I'm sure NRL fans in Perth and in North Sydney will join me in welcoming him with open arms," De Ceglie said.
"He is an icon whose leadership qualities such as courage, honesty and hard work are rightly renowned across the country."
