Objective To investigate the value of cervical vascular color Doppler ultrasound and MRI in detecting the carotid artery stenosis in patients with cerebral infarction. Methods The clinical data of 100 patients with cerebral infarction admitted from January 2016 to January 2017 in our hospital were retrospectively analyzed. All patients underwent color Doppler ultrasound examination firstly, then receiving MRI examination. Results A total of 119 cases of cervical vascular plaque were detected by color Doppler ultrasound, of which 85% occurred at the bifurcation of common carotid artery and 25% occurred at the beginning of carotid artery. There were 6 cases of lacunar cerebral infarction and 13 vessels in the lesion. The small size cerebral infarction occurred in 78 case, including 31 vessels in the lesion. The large size cerebral infarction occurred in 35 case, including 12 vessels in the lesion. The vascular ultrasound examination results of three groups had significant difference (Z=-15.614, P=0.000). A total of 148 cases of carotid artery stenosis were detected by MRI, of which 18 were lacunar cerebral infarction (9 vessels in the lesion), 86 cases were small and medium size cerebral infarction (89 vessels in the lesion), and 41 were large size cerebral infarction (41 vessels in the lesion). The artery stenosis rate of three groups had significant difference (P<0.05). The vascular color Doppler ultrasound examination results of three groups also had significant difference (Z=-11.194, P=0.000). Conclusion Both cervical vascular ultrasound and MRI can detect the degree of carotid stenosis in patients with cerebral infarction and predict the status of cerebral infarction. While the MRI can better determine the plaque location, size, shape of the carotid artery stenosis, which can improve the carotid artery stenosis detection rate.