Objective: To explore the relationship between an anti epidemic mentality and post traumatic stress disorder (PTSD) among college students during the corona virus disease 2019 (COVID-19) pandemic, and to provide a scientific basis for the prevention of PTSD when college students experience sudden crisis events in the future. Methods: An online questionnaire survey was conducted among 9 399 undergraduates from Shanxi Medical University using the Posttraumatic Stress Disorder Checklist Civilian Version (PCL-C) and the public anti epidemic psychology self examination scale. Results: During the COVID-19 pandemic, the total PCL-C scores of college students were (22.74±7.78), and the positive rate of PTSD symptoms was 5.3%. The detection rates of symptom recurrence, avoidance/numbness symptoms and increased alertness symptoms were 27.0%, 16.6% and 8.6 %, respectively. The average score of avoidance/numbness symptoms in the three symptom groups was (9.21±3.39), the two items with the highest scores were repeated recall of traumatic events (1.57±0.71) and impaired concentration (1.47±0.71). Females scored higher than males on the increased alertness dimension(6.82±2.61，6.67±2.72) ( t = -6.49 ， P <0.05). In respect to PCL-C total scores and the scores of each dimension, rural areas were associated with higher scores than urban areas, and non medical students scored higher than medical students, while the scores of those who grew up with siblings were higher than only children ( P <0.05). There was a significant positive correlation between an anti epidemic mentality and total PTSD scores ( r =0.51, P <0.01). Multiple regression analysis showed that the place of origin, choice of college major, and antiepidemic mentality were predictors of PTSD symptoms ( P <0.01). Conclusion Anti epidemic mentality is associated with the occurrence of PTSD among college students.