Plaque compositional features are effective indicators for vulnerability and associated with ischemic stroke risk. Multicontrast vessel wall imaging has been utilized to characterize plaque compositions but this technique is time consuming and dependent on reviewer’s experience. Therefore, it is important to characterize plaque compositions with time-efficient imaging approach. This study sought to determine T1 values of carotid plaque components determined by quantitative imaging validated by histology. We found that the T1 values of intraplaque hemorrhage, necrotic core, and loose matrix were distinguishable. Our findings suggest that carotid plaque components might be distinguishable and automatically segmented on quantitative MR imaging.