The services have been legal since last summer under temporary legislation that expires next month, reports Xinhua news agency.
The Drug and Substance Checking Legislation Bill (No. 2), which passed its third reading and will come into effect on December 7, means services can now continue and be expanded as required, Little said in a statement.
"This legislation is about keeping people safe," he said, adding that the current drug-checking services have detected and intercepted potentially deadly substances circulating in the community.
Evidence shows that when people are told substances are not what they think they are, they'll often choose not to take them, potentially saving lives, Little said.
Research by the Wellington-based Victoria University on behalf of the Ministry of Health showed that 68 perc ent of festival-goers who used drug-checking services said they had changed their behaviour once they saw the results, said the Minister.
The government has also approved three new organisations to perform drug-checking services.
The New Zealand Drug Foundation, the NZ Needle Exchange Program and the Institute of Environmental Science and Research (ESR) will work alongside existing provider KnowYourStuffNZ.
The government is also contributing NZ$800,000 towards the cost of the service, Little said.