They found 3.9 tonnes of ephedrine, a vital ingredient in the production of methamphetamine, at the Port Botany container examination facilities.
The find is more than double the size of the previous record. The largest amount of ephedrine ever caught being imported into New Zealand is 200kg.
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The ephedrine was hidden amongst 1000 cartons of iced tea. About 350kg of methamphetamine was also found in drums of liquid plaster solution.
The techniques used to hide the drugs have been described as "sophisticated".
"Organised criminals, they change their methodology according to our tactics and methods and that game continues on, but this was a pretty sophisticated concealment methodology," Acting Commissioner Michael Outram of the Australian Border Force said.
Two men and a woman were arrested after raids at properties in Cabramatta, Rydalmere, Westmead and Revesby.
The trio have been denied bail and face up to 25 years in jail.