Purpose: To investigate the accuracy of 64-row MDCT to analyze and quantify coronary arterial plaques in patients presented with acute coronary syndrome (ACS). Patients and methods: Between April 2010 and December 2013, 50 patients presented with acute cardiac chest pain were categorized into 2 groups according to their diagnosis based on clinical evaluation, ECG findings and cardiac biomarkers; group A including patients with ACS and group B including patients with stable angina (SA). Both groups underwent 64-row multidetector CT (MDCT) coronary arterial imaging. For each plaque, stenosis percentage was evaluated and the plaque was quantified using software (Sureplaque®) based on the density (HU) and percentage of its individual components including lipid, soft tissue, and calcium density. Results: Of the 50 patients; 24 and 26 were grouped into groups A & B respectively. The mean value of stenosis percent of the proximal & middle  coronary segments of group A patients = 77.2% ± 10.2% - 90.5% ± 58.4% and 79.5% ± 9.1% - 85.25% ± 11% respectively, while in group B = 54.1% ± 12.1% - 65.2% ± 18.4% & 53.3% ± 1.5% - 68.6% ± 11.7% respectively (p=0.00-0.001). Quantification showed a mean value of lipid content percentage of group A = 15.4% ± 0.8% - 47.7 % ± 19.2 %, while in group B = 7.2% ± 5.5% - 10.3% ± 8.2% (p=0.008–0.001). The mean value of soft tissue content percentage in group A = 15.4% ± 0.8% - 47.7 % ± 19.2 %, while in group B = 7.2% ±5.5% - 10.3% ± 8.2%. The calcification content percentage in group A = 18% ± 8.7% - 35.1 % ± 16 %, while in group B = 66.4% ± 13.8% - 76.7% ± 16.5%. Conclusion: 64-row MDCT angiographic quantification software provides a good basis for the future attempts of proper risk stratification of patients with coronary artery disease especially those liable for developing ACS.