Police Detective Inspector Bruce Good said it was a hefty amount of the drug.
"This is a huge amount that had the potential to cause serious social harm to our community," he said.
"Unfortunately though, the demand for ephedrine will remain high and we will continue to target the organised criminal groups supplying and selling ephedrine."
Customs spokesman Jamie Bamford said it was about breaking the illicit supply chain.
Customs has several systems in place to target shipments of illegal drugs before they arrive on New Zealand shores, he said.
"We'll continue to work closely with Police and other agencies to catch the criminals involved."
Police urge anyone with information on drug dealing in their community to contact them. Information can be given anonymously via the Crimestoppers organisation on 0800 555 111.