Background: Road traffic crashes (RTCs) can cause serious and long-lasting consequences for drivers, both in terms of physical and mental health outcomes. Posttraumatic stress disorder (PTSD) is the most frequent mental disorder occurring after traumatic exposure. Ethiopian drivers experience RTCs more frequently than other sub-Saharan countries. Despite this prevailing phenomenon, limited attention has been given to PTSD among drivers. Objective: To determine the prevalence of PTSD and associated factors among drivers surviving RTCs in southwest Ethiopia. Methods: A cross-sectional quantitative study was conducted among 402 male drivers who had survived RTCs. The study was conducted in Jimma zone, southwest Ethiopia from March to June, 2019. All drivers who had survived RTCs in the last year were included in the study. The Trauma Screening Questionnaire was used to determine the prevalence of PTSD. Data were entered in EpiData 3.1 and exported to SPSS 24 for analysis. Results: The response rate of the study was 398(99%). Fifty of 398 (12.6%, 95% CI 9.5%-16.1%) met PTSD criteria based on the questionnaire. A history of near-miss RTCs (AOR 3.49, 95% CI 1.89-6.43), depression (AOR 3.32, 95% CI 1.36-5.12), and severe-risk cannabis use (AOR 2.51, 95% CI 1.96-7.52) were significantly associated with PTSD. Conclusion and recommendation: The prevalence of PTSD among drivers surviving RTCs was high compared to the general population. A record of near-miss RTCs, depression, and severe-risk cannabis use shown significant associations with PTSD. Strategies and guidelines must be developed to screen and treat PTSD among drivers surviving RTCs. Drivers with experience of near-miss RTCs, depression, and severe-risk cannabis use should be given priority when screening for PTSD.