{L-End}Objective To analyze the current status of post-traumatic stress disorder (PTSD) among firefighters in Chongqing City and explore its influencing factors. {L-End}Methods A total of 1 021 firefighters in Chongqing City were selected as the study subjects using the convenient sampling method. The PTSD Checklist Civilian Version was used to assess their PTSD symptom and characteristics. The Trait Coping Style Questionnaire and the Social Support Rating Scale were used to investigate coping styles and the level of social support. {L-End}Results The positive detection rate of PTSD among the study subjects was 4.6%(47/1 021), with positive detection rates of re-experiencing, avoidance/numbing, and hyperarousal symptoms of 7.0%, 9.2%, and 16.5%, respectively. The positive detection rates of re-experiencing, avoidance/numbing, and hyperarousal symptoms in the PTSD firefighters were higher than those in non-PTSD firefighters (83.0% vs 3.3%, 93.6% vs 5.1%, 100.0% vs 12.1%, respectively; all P<0.01). The results of the multivariate logistic regression analysis showed that being injured in the past six months and adopting a negative coping style were risk factors for PTSD ［odds ratio (OR) and 95% confidence interval (CI) were 2.65 (1.07-6.56) and 1.26 (1.19-1.33), respectively; both P<0.05］, while adopting a positive coping style and having a higher level of social support were protective factors for PTSD ［OR and 95%CI were 0.90 (0.85-0.95) and 0.95 (0.91-0.99), respectively; both P<0.05］. {L-End}Conclusion The incidence of PTSD among the firefighters in Chongqing City is relatively high, with symptoms mainly characterized by hyperarousal. Being injured in the past six months, coping styles, and the level of social support are influencing factors for PTSD.