The nuclear accident in Fukushima triggered a process of regulatory action, inspections, and market restrictions that has deeply affected the Japanese food market. When higher than permissible levels of radioactivity entered the food chain, the Japanese Government had to take strong measures to protect consumers.At the same time, it had to explore ways to avoid disproportionate penalties on the producers from the affected region. This article examines Japan's regulatory response to the nuclear accident and the legal instruments the government accordingly employed. Our analysis follows four regulatory steps that were taken by the government to safeguard the food chain: the establishment of maximum permissible levels for radioactive levels in food; the adoption of guidelines on how to monitor these levels; the restriction of the distribution and consumption of excessively contaminated food and, finally, where and when possible, the lifting of these restrictions.