To investigate changes in the general mental health of individuals before and during the COVID-19 epidemic and psychological stress they generate. Methods: The Chinese version of the General Health Questionnaire (GHQ-12) and the Stress Response Questionnaire (SRQ) were used to investigate the mental health status and stress response before and during the epidemic for 520 selected residents. The Chi-square test, nonparametric Z-test, and Spearman correlation analysis were used for data analysis. Results: After the outbreak, the detection rate of suspected mental health disorders increased to 23.46% (122/520), and this increase was more prominent in the anxiety/depression dimension．There were significant differences in the GHQ-12 total score, SRQ total score, and various factor scores. Results of the Spearman correlation analysis on individuals’concern toward the epidemic and GHQ-12 and SRQ total scores and various factor scores showed a positive correlation between level of concern and GHQ-12 total scores, anxiety/depression factor scores, SRQ total scores, emotional response factor scores, and body response factor scores. Conclusion: The COVID-19 epidemic has brought about a growth in suspected psychological disorders, increased the level of individual stress, and adversely affected the individual's mental health, particularly emotional health. Individuals' excessive concern about the epidemic may increase their level of stress and is not conducive to maintaining mental health．