Objective To investigate the mental health status and correlation factors of medical staff 1 year after the outbreak of COVID-19 to take appropriate psychological interventions

in order to protect the health of medical staff. Methods An online questionnaire was distributed to the medical staff of medical institutions at all levels in Guangdong province

including sociodemographic characteristics

the general health questionnaire（GHQ-12）

and simplified post-traumatic stress disorder（PTSD） checklist 6-item（PCL-6）. Data were collected and statistical analyses on various indicators were performed. Results A total of 600 questionnaires were distributed and 519 valid questionnaires were collected. The detection rate of PTSD was 39.24%（144/367） in respondents from primary care institutions

which was lower than that in respondents from general hospitals（51.32%

78/152）

and the difference was statistically significant（χ~2=6.406

P=0.011）. Logistic regression results showed that whether there were minor children at home（OR=3.139; P=0.004） and hospital level（OR=3.902; P=0.009） were the influencing factors of emotional distress in respondents. The hospital level（OR=2.340; P=0.019）

working years of 6-9 years（compared with working years ≤ 5 years）（OR=0.396; P=0.021） and gender（OR=0.590; P=0.028） were the influencing factors of PTSD in respondents. Conclusion Organizations and government agencies can provide appropriate psychological support for those at high risk of mental problems to alleviate the distress.