Introduction: Acute traumatic coagulopathy (ATC) is defined as having evidence of coagulopathy in patients with severe trauma. The aim of this preliminary study was to assess the prevalence and associated factors of ATC in severely traumatic patients presenting to emergency department (ED). Methods: In this retrospective cross sectional study, all patients with severe traumatic injury and available coagulation profile, presenting to the EDs of two major trauma centers in Tehran, Iran, during one year, were studied. Rate of ATC was determined and the associations with various variables as well as outcome were analyzed using SPSS 21. Results: 246 patients with the mean age of 36.57±17.11 years were included (88.2% male). The mean injury severity score (ISS) was 21.83 ± 7.37 (16 – 54). Patients were resuscitated with 676.83 ± 452.02 (0 – 1500) ml intravenous fluid before arriving at the ED. The maximum and minimum frequencies of ATC were 31.3% based on PTT > 36s and 2.4% based on PT > 18s, respectively. There was a significant association between the occurrence of ATC (PT ratio > 1.2) and ISS > 23 (p = 0.001), abdominal abbreviated injury score (AIS) > 3 (p = 0.003), base deficit > 4 (p = 0.019), pulse rate > 90/minute (p = 0.041), and pH < 7.30 (p = 0.043). Conclusion: The frequency of ATC in the present series varied from 2.4% to 31.3% based on different ATC definitions. Abdominal AIS > 3 and base deficit > 4 were among the significant independent factors related to ATC occurrence based on stepwise logistic regression analysis.