Abstract: Background:In Iraq, trauma is one of the primary causes of death. The abdomen is one of the most sensitive body areas to such injuries. Focus Assessment with Sonography in Trauma(FAST) is a noninvasive bedside method for detecting free fluid in the peritoneal and pericardial cavity. Objective:To assess the accuracy of free fluid diagnosis in the peritoneal cavity utilizing FAST scan conducted by Emergency Medicine physicians versus. Radiologists Patients and Methods:A prospective observational diagnostic accuracy research comparing FAST scan reports from emergency medicine residents versus radiology residents in the emergency department was conducted .Characteristics such as sensitivity, specificity, positive predictive value, and negative predictive value were used to compare the accuracy of the two groups by comparing them to CT scan reports and the patient's clinical status, which were considered the gold standard for diagnosing free fluid. Results:The sensitivity of emergency medicine residents in detecting free fluid in the abdomen by using FAST was 82% compared to 100% in radiology residents. The specificity of emergency medicine resident was 98.6% similar to that of radiology residents. We also found that there is a substantial level of agreement between both groups (Kappa= 0.789). Conclusion:Emergency Medicine Residents were able to execute FAST on patients with blunt abdominal trauma with excellent accuracy. We conclude that FAST scans performed by emergency medicine residents had acceptable diagnostic results Keywords: Abdominal blunt trauma, FAST scan, Emergency medicine