Objective: To investigate the diagnostic value of spectral CT reconstruction mode for carotid atherosclerotic plaque lesions. Methods: From January 2017 to January 2019, 70 patients with carotid atherosclerotic plaque lesions in our hospital were selected as the research object. All patients were diagnosed with cervical vascular color Doppler ultrasound and spectral CT scan under spectral CT reconstruction mode. Taking the results of coronary angiography as the “gold standard”, the clinical value of the two examination methods in the diagnosis of carotid atherosclerotic plaque lesions was compared and analyzed. Results: Coronary angiography diagnosis confirmed that 33 of 70 patients with suspected carotid atherosclerotic plaque lesions had vulnerable plaques and 37 had stable plaques. The accuracy of Spectral CT examination of carotid artery plaque was 87.14% (61/70), sensitivity was 90.91% (30/33), specificity was 83.78% (31/37), and the positive predictive value was 83.33% (30 /36), the negative predictive value is 91.76% (31/34), which is higher than that of cervical vascular ultrasonography (61.43%, 60.61%, 56.76%, 57.89%, 65.63%), the difference is statistically significant (P<0.05). Conclusion: The application of Spectral CT in the clinical diagnosis and treatment of carotid atherosclerotic plaque lesions with higher accuracy, sensitivity and specificity, is more significant and can provide a more reliable and effective imaging basis.