Legislation amending the Emissions Trading Scheme passed its second reading in Parliament by a very narrow majority on Thursday.
Changes include keeping agriculture out of the scheme indefinitely and allowing polluters to import unlimited foreign carbon credits.
The Government's bill passed by 61 votes to 59 with the support of National, ACT and United Future.
Opposition parties say the bill ignores the pleas of carbon farmers being hit by record low prices.
Labour says the low prices are destroying the local industry and will make it harder in the future for New Zealand to meet its international obligations to cut carbon emissions.
The bill will come back to Parliament next month for a clause-by-clause debate before its third and final reading.