Gregg Wycherley, managing director of Auckland's Fresco Nutrition, which is preparing to launch its goat-milk infant formula in China, said he hoped the policy change - combined with 2014 being the auspicious year of the horse - would result in a spike in the Chinese birth rate.
"From a business point of view it could only be helpful for New Zealand infant formula manufacturers," Wycherley said.
Chairman of the New Zealand Infant Formula Exporters Association, Michael Barnett, said the prospect of China's infant formula market becoming even bigger was good news.
The US$12.4 billion ($15.13 billion) Chinese infant formula market is expected to double in size by 2017, according to Euromonitor data compiled before the policy change.
The August botulism false alarm spooked many Chinese consumers, but Barnett said there had been some recent improvements in the trading conditions facing Kiwi baby formula firms. However, there would be "one or two casualties" stemming from the contamination debacle by the end of this year.
The one-child policy applies to only about a third of China's population, with ethnic minorities exempt and rural Chinese already allowed a second child.
China's Government claims the country's population - around 1.3 billion - would be 400 million higher if the policy had not been introduced in 1979.
Many Western experts have disputed that calculation, saying the actual figure is likely to be closer to 100 million.