"There's lots of complicated needs for these kids and they've been there making sure they get what they need.
"These guys are at the coalface - they are not particularly rich people, just ordinary people doing an extraordinary job."
Mr and Mrs Burrows care full-time for three foster children aged 12, 9 and 8, while Mr and Mrs Walker care full-time for two children, aged 5 and 3.
Mrs Burrows said she and her husband were blown away when they heard they had been selected for the award.
"We kept looking at each other and bursting out laughing. You don't do it for the recognition but it's really nice to be recognised, because it's not an easy job.
"You've got to do it for the love."
Her parents had been foster parents and it had seemed like a natural decision to continue the tradition, she said.
The couples agreed that although it can be a tough job, the rewards of being a foster parent far outweigh the difficulties.
Mr Walker said one of the joys of being a foster parent was watching the children become more secure and confident. "One of the highlights is seeing them hit the targets that you would expect in a 'normal' family.
"They don't have to be Einstein proteges but we have expectations of them."
The awards will be presented on Friday at Government House. The four will be treated to a stay at a hotel as part of their prize.