The Australian Federal Police say they have made the fifth largest heroin seizure in Australian history.

Three people were arrested in Campsie in Sydney's west on Saturday for allegedly attempting to import 168 kilograms of heroin.

The operation began almost two weeks ago when customs officers in Sydney discovered packages of heroin hidden inside a number of wooden doors shipped from Malaysia.

The Australian Federal Police then allowed the doors to be delivered to a warehouse in the city's west.

They allege a 55-year-old woman and her 28-year-old son, along with a 33-year-old Hong Kong national removed the heroin from the doors and took them to a house nearby.

All three were arrested the next evening.

The woman will face Sydney's Central Local court this morning.

The value of the heroin is believed to be about $58.8 million but Commander David Stewart says, depending on its purity, its street value could be much higher.

"If it's over 70 per cent, it has the potential to yield anything up to or over $410 million, but that depends on how many times that it's cut down to street level," he said.

"Now street level could range from anywhere between 7 per cent to 11 or 12 per cent."

Commander Stewart says the seizure has saved the community millions in health and social costs.

"This operation highlights the commitment and cooperation of law enforcement to acting quickly to investigating organised criminal groups," he said.