The Ministry of Agriculture and Forestry says it is confident no contaminated food from Japan will reach New Zealand.
The Fukushima Daiichi nuclear power plant was badly damaged after a 9.0-magnitude earthquake triggered a tsunami that devastated the northeast coast of Japan on 11 March.
The United Nations' International Atomic Energy Agency says the overall situation at the facility remains very serious and the source of radiation still being emitted has not been identified.
The Japanese government says above-safety radiation levels have now been discovered in 11 types of vegetables from the Fukushima area.
It has ordered two prefectures near the plant to halt shipments of vegetables and other foods found to have radiation levels up to 164 times the legal limit.
Radiation has also been found in milk, tap water and the Pacific Ocean, although the government and experts insist that the levels are still far from dangerous to humans. Tokyo residents have been told not to give their babies tap water after unsafe levels of radioactive iodine were detected.
MAF spokesperson David Crowe says the little food New Zealand imports from Japan is mostly processed, such as sake, soy sauce, pickled ginger and wasabi.
Mr Crowe says the ministry is confident that the processes Japanese food safety authorities have in place are adequate and New Zealand's monitoring systems will be stepped up if it is deemed necessary.
The United States has halted food and milk imports from areas near the crippled nuclear plant.
Many calls from concerned public
MetService and the National Radiation Laboratory have received numerous calls from members of the public concerned that the nuclear emergency in Japan could affect New Zealand.
MetService spokesperson Peter Kreft says the calls started a short time after the nuclear crisis began and staff have been assuring callers that they do not need to be worried about nuclear fallout in New Zealand.
Atmospheric circulation patterns will confine any radioactive material from Japan to the northern hemisphere, he says.