Background: A large number of individuals visit an emergency department (ED) complaining of chest pain that cannot be diagnosed, which remains a formidable clinical challenge. Objectives: In this study, we set out to determine how useful triple rule out (TRO) MSCT angiography is for diagnosing acute chest pain (ACP) in patients who are present to the emergency room. Patients and Methods:  This study was conducted on 50 patients, presented to ED and the cardiac care unit (CCU) complaining from ACP. 12-leads an electrocardiography (ECG) examination, cardiac enzymes (Troponin, CKMB) and TRO CT angiography were assessed to all patients. Results: Thirty patients were diagnosed with ACS, four patients were diagnosed with aortic aneurysm, the diagnosis in another four patients was pulmonary embolism, six patients were normal, and another six patients have a non-vascular cause. There was highly statistically significant relation between diagnosis as regard coronary angiography and CTA TRO (p<0.05). There was highly statistically significant relation between diagnosis as regard coronary angiography and TRO CT angiography (p <0.05). CTA TRO can diagnose ACP with sensitivity 93.75%, specificity 50%, positive predictive value 93.75%, negative predictive value 50% and diagnostic accuracy 88.89%. Conclusions: An appealing option is the TRO protocol, which can be used to avoid all three possibly deadly reasons for acute chest pain with a single scan. This is particularly true for older patients who have a relatively lower risk of radiation-induced cancer, and for emergency department patients with atypical chest pain who are not at high risk.