We aimed to (1) describe the subjective well-being (SWB) of older residents in Fukushima Prefecture seven years and seven months after the Great East Japan Earthquake (GEJE) and examine the effect of relocation to the restoration public housing (RPH) on SWB, social capital, and health indicators; and (2) investigate the association between social capital and SWB. Questionnaires were administered to collect data of both RPH and non-RPH residents (≥65 years). Respondents’ SWB was collected via the Japanese version of the World Health Organization Five Well-Being Index. Additionally, residents’ social capital (trust, reciprocity, and participation), physical activity level, social network, functional health, history of chronic disease, and demographic data were collected. We analyzed 101 responses (valid response rate: approximately 34%) from RPH and 158 (53%) from non-RPH residents. SWB was lower in RPH compared to non-RPH residents but not statistically significant. Older RPH residents may demonstrate lower social capital and health indicators after the GEJE. Mistrust was found to be positively associated with low SWB in RPH residents. Future studies should examine the effectiveness of support for enhancing the trust of older RPH residents regarding, for example, the involvement of scientists—including medical professionals—in risk communications in promoting SWB.