Objective:To investigate the level of psychological stress, anxiety and posttraumatic stress disorder (PTSD) of military medical students under the condition of normalized prevention and control of the epidemic.Methods:A total of 225 students from a military university were selected by random sampling method. Chinese perceived stress scale (CPSS), Perceived social support scale (PSSS), Self-rating anxiety scale (SAS) and PTSD Checklist-5 (PCL-5) were used to measure the mental health of the subjects and influencing factors. SPSS 26.0 was used to conduct independent sample t test and ANOVA analysis. Pearson correlation analysis was conducted, and multiple regression equation was used to further analyze the relationship between psychometric factors. Results:The SAS scores of 22.2% (50/225) of the subjects and PCL-5 scores of 30.7% (69/225) of the subjects reached the positive standard. The results of correlation analysis showed that the total score of PSSS was negatively correlated with CPSS ( r=-0.315, P<0.01), SAS ( r=-0.336, P<0.01) and PCL-5 ( r=-0.137, P<0.05) scores. The score of family support negatively predicted the level of psychological stress ( B=-0.595, P<0.001), anxiety ( B=-0.635, P<0.001) and PTSD level ( B=-0.769, P=0.006) of the students. Conclusion:Social support, especially family support, has a significant protective effect on psychological stress, anxiety and PTSD during the period of normalized prevention and control of the epidemic.