This study aimed to examine the status of depression symptoms and occupational stress factors that triggered these symptoms among workers in medical and welfare industries. Web-based surveys were conducted in 2016 and 2019 among research company survey respondents regarding their work, life and health. This study extracted data for medical services and welfare workers who participated in both the initial survey in 2016 and the follow-up survey in 2019. First of all, 288 regular employees (221 men and 67 females of mean age 45.6 years, SD = 9.0) who worked in the medical services and welfare industries at the time of both surveys were identified. Of these, 115 presented with depressive symptoms by CES-D scale (39.9%), indicating a higher ratio compared to other occupations. Following this, for the 173 respondents who did not present with depressive symptoms in the initial survey but developed depressive symptoms during the three years following the initial survey, changes (favorable, improved, no change, deteriorated, unfavorable) in occupational stressors were analyzed using explanatory variables. As the results of logistic regression analysis, at the time of the follow-up survey, 32 respondents presented with symptoms of depression (18.5%), and environmental work stress (noise, lighting, temperature, ventilation, etc.) and interpersonal stress at work (unfavorable stress conditions at the time of both surveys) significantly affect the onset of these symptoms. Many medical services and welfare workers are required to suppress their own emotions as they go about their busy daily duties of caring for others, and this study suggests that they are working under highly stressful conditions. There is a strong sense that the workplace has reached an impasse, and a new approach is needed in a bid to revitalize the organization and create attractive company structures, as well as improve the physical working environment.