The Western Australia state capital's new team will kick off in 2006.
Perth joins Australia's three established teams in the current Super 12 competition - ACT Brumbies, NSW Waratahs and Queensland Reds.
The Perth bid had secured total pledged sponsorship of more than A$4 million, with the likes of the Kerry Packer-controlled Burswood Casino on board.
This was in addition to the $2 million-plus in committed corporate hospitality, a $25 million government backed upgrade of the Members Equity Stadium home ground and some very public support from Wallabies captain George Gregan.
ARU chairman Bob Tuckey paid tribute to both the Victorian and the Western Australian rugby unions and their respective state governments, for their outstanding submissions.
"This is an historic day for rugby in Australia," Tuckey said.
"The Board was faced with an extremely complex decision based on detailed analysis of two compelling bids. Each had great merit but only one could be chosen on this occasion."
ARU Managing Director Gary Flowers emphasised that no single criteria determined the outcome, but rather the submissions were judged across a range of criteria that led to the ARU Board forming a view.
"Just as I urge Western Australians to now embrace this opportunity, equally I urge the Victorian rugby community to continue the work which has seen rugby thrive in their state."
A management team will shortly be appointed with its first task to employ a chief executive.
