Climate Change Minister Paula Bennett said today such a move would be "a real shame" given US leadership on the issue and its responsibility for a large proportion of global emissions.
"It would be a big deal, quite frankly, if any of the big emitters pulled out," Bennett said.
Former Prime Minister Sir Geoffrey Palmer went further, saying a Paris Agreement without the US would "spell disaster" for global efforts to prevent runaway climate change.
Trump has previously spoken about climate change being a "hoax" and says he wants the United States to rebuild its coal industry, against the warnings of scientists who say most fossil fuel reserves must remain in the ground if harmful climate change is to be avoided.
New Zealand's former climate change negotiator Adrian Macey said Trump's scepticism made him an outlier among international leaders.
But while his climate policies were "not good news", they were not a cause for despair, Macey said.
"The economics are starting to make sense with wind and solar energy costs coming down, so there are other long-term trends happening which go way beyond the four years of an American presidency."
Professor of Strategic Studies Robert Ayson, of Victoria University, said a Trump Presidency was unlikely to reverse the growing NZ-US relationship.
But New Zealand might be expected to do more in its own backyard under the new president, he said.
"In the case of an event in the South Pacific or even north of Australia, the US might delegate the role to us," Ayson said.
Trump has criticised the US' traditional allies and others for not pulling their weight on international affairs and defence.
Of greater concern was the broader movement which Trump was a part of, including Brexit, which challenges the open, tolerant democratic system which New Zealand belongs to.
"This is the big concern, that the fabric of domestic and international society as we know it - that's not so sure anymore," Ayson said.
"Bit by bit the commitments to these values and to these ways of doing things politically are being chipped away.
"That's the thing that bothers me and that's not good for New Zealand at all."
New Zealand was one of the "bastions of reason", he said, but "the islands of reason are being surrounded by bigger seas of unreason".
Parliament passed a motion to congratulate Trump on his election victory this afternoon.
It was supported by all parties except the Greens, who said they could not approve of a racist, sexist candidate.