This study was to clarify how work-from-home and telework, which were rapidly introduced in 2020 due to the impact of COVID-19 pandemic, caused workers to experience changes in their work and personal lives, and to examine the relationships between these changes and psychological indicators. Semi-structured interviews about changes in work and personal life caused by working from home were first conducted with 56 Japanese workers who worked from home for the first time beginning in January 2020, and survey items were created from the responses. An internet survey was then conducted on 923 Japanese workers who started working from home for the first time when the state of emergency was issued in April 2020. Factor analysis was conducted, and 7 factors (with 64 items) were extracted: “difficulty in work” “easy to get work-life balance”, “improvement of the working relationships”, “improvement of the relationships with family”, “interference from families during work”, “becoming long work hours”, and “difficulty in evaluating subordinates”. Relationships between these subscales and job stressors, job resources, stress reactions, positive outcomes, work-life balance, and work-family conflicts were examined. Results indicated that long work hours were positively correlated with quantitative job demands, that work-from-home may improve work-related interpersonal relationships, and that improvement of the relationships with families may increase the positive spillover between work and home.