The Government Communications Security Bureau is investigating attempted cyber attacks on the National Institute of Water and Atmospheric (NIWA) research's super computer.
NIWA said late last week there were several unauthorised attempts to access its supercomputer, which was used to run scientific models and services.
Prime Minister John Key said the number of cyber attacks was growing considerably, with more than 200 recorded in the past year.
He said those attacks were monitored by the national cyber security centre, which was part of the Government Communications Security Bureau.
"The IP address in this particular case was China, although that doesn't mean at all it's from a Chinese entity," Mr Key said.
"It could well be being used as a mask, if you like, for the ultimate body that's behind that."
Mr Key said there is no obvious motive to the attempt cyber attack on NIWA.