A $15 million, 37-bed paediatric ward will be built at Joondalup Health Campus to take pressure off the yet-to-be-completed Perth Children's Hospital.
The new ward, to be named the Telethon Kids Ward, will replace the hospital's 24-bed paediatric ward and help grow the number of paediatric beds in WA from 339 to 406 by 2016.
Health Minister Kim Hames said the new ward was part of the State Government's plan to take high-quality care closer to where families were living.
Dr Hames said the biggest demand for paediatric beds was in the rapidly growing northern and southern metropolitan areas and the ward would establish Joondalup Health Campus as a "mini hub" for paediatric care, while Fiona Stanley Hospital would be the southern "mini hub".
He said a significant amount of the care that had traditionally been provided at Princess Margaret Hospital could be better provided in outlying hospitals.
He believed having first-class facilities and doctors at hospitals in Perth's outer suburbs would make parents more comfortable with the idea of taking their children there rather than to the central children's hospital.
"As we said when we were talking about the Perth Children's Hospital, we needed to grow our peripheral beds for children," Dr Hames said. "This is the first stage of doing that.
"We still need Princess Margaret, and now Perth Children's Hospital, for tertiary care - that very high-end care, particularly patients with cancer - but a large number of patients that go there now could quite easily be treated here."
Australian Medical Association WA president Richard Choong, who has criticised the Government's decision to not add an extra storey to the $1.2 billion Perth Children's Hospital, welcomed the announcement of the expanded paediatric ward because it would provide care for children closer to home.
But Dr Choong said the ward would not satisfy Perth's growing need for tertiary-level paediatric beds.
"As our population grows bigger and we have more children, they will require more specialist services," he said.
"I welcome the introduction of the new paediatric ward for Joondalup, as it will allow the delivery of paediatric care closer to home, but still it does not replace the need for more beds in the tertiary paediatric hospital.
"That would have allowed us to truly futureproof Perth's paediatric services."
The Telethon Kids Ward will have overnight facilities for parents and a 10-bay day procedure unit and three-quarters of its beds will be in single rooms.
It is being jointly funded by the State Government and Telethon WA, with each to contribute $6 million, and Ramsay Health Care will chip in $3 million.
Channel Seven Telethon Trust chairman Kerry Stokes said Telethon prided itself on making children's lives better and the new paediatric ward would usher in a new era for the Joondalup area.