We investigate what are the factors that influence people’s intent to return after disasters by a literature survey, and conduct an empirical analysis on return migration by using a unique survey of Fukushima evacuees to determine the factors that influence their decision to return after a disaster. We also conduct a simulation of the number of evacuees who intend to return. The result found that the number of returnees encouraged by this decontamination was 12,882, less than 8% of the total evacuees, while the decontamination cost per returnee was 3.36 million USD.