Coronavirus disease 2019 (COVID-19) has been a global challenge ever since its emergence, with reports suggesting negative effects of the pandemic on the mental health and well-being of people worldwide. Thus, in this study, we investigated the associations among the socioeconomic changes driven by the pandemic, mental health, life satisfaction (past, present, and future), and fear of COVID-19 in Japan. In total, 560 Japanese individuals took an online survey that included questions on their self-restraint and changing incomes and the Fear of COVID-19 Scale; Depression, Anxiety, Stress Scale; and present, past, and future life satisfaction scale. Two structural equation models were constructed, revealing that fear of COVID-19 brought about reduced times outdoors, reduced incomes, negative symptoms, and negative present, future, and past life satisfaction.