More than 70 children in Western Australia are currently under the care of foster carers who do not have a valid Working with Children (WWC) Check, it has been revealed.

Child protection officials told a budget estimates hearing that, as of April, carers of 76 children did not have a current WWC clearance.

That included 19 children living with department carers and 57 who were under the care of relatives.

The State Opposition accused the WA Government of putting children at risk by failing to make sure all foster carers were adequately screened.

However Child Protection and Family Support director general Emma White said the figure included carers whose clearance had simply expired, as well as those used in urgent situations.

"There are certain circumstances, mostly within an emergency context, where children can be placed with foster carers — generally relative carers — for a prescribed period of time without a check," Ms White said.

"Before we would do that ... or make that consideration we would put a number of safeguards in place."

Ms White said relative carers did not consider themselves foster carers for the Department of Child Protection.

"They're looking after their own children, their own family children, so the thought of we have to keep going through what can be seen as quite administrative or bureaucratic processes ... is sometimes difficult for a relative carer to prioritise," she said.

But Labor Child Protection spokesman Stephen Dawson said it was a major concern that some of the carers had never had the clearance.

"The State Government should be leading by example," he said.

"[It] should be ensuring that every person... has a Working with Children Check so we can have some level of confidence that those kids are properly protected."

"We can have no confidence that people who have criminal records could potentially be caring for children, and that is putting children at risk."