Background: Associations between nuclear disasters and suicide have been examined to a limited extent. Aim: To clarify the suicide rates in evacuation areas after the nuclear disaster in Fukushima, which occurred in March 2011. Method: This descriptive study used monthly data from vital statistics between March 2009 and December 2015. Suicide rates in areas to which evacuation orders had been issued, requiring across-the-board, compulsory evacuation of residents from the entire or part of municipalities, were obtained and compared with the national average. Results: Male suicide rates in evacuation areas increased significantly immediately after the disaster, and then began to increase again 4 years after the disaster. Female suicide rates declined slightly during the first year and then increased significantly over the subsequent 3-year period. Moreover, male rates in areas where evacuation orders were issued for the total area declined over the course of approximately 2 years, but then began to increase thereafter. Analysis by age revealed postdisaster male rates in evacuation areas decreased for those aged 50–69 years and increased for those aged ≤ 29 years and ≥ 70 years. Limitations: The number of suicides among females and the female population in the evacuation area was small. Conclusion: Our findings suggest the need to keep in mind that, when providing post-disaster mental health services, suicide rates can eventually increase even if they initially decrease.