Objective To investigate the value of high-resolution magnetic resonance angiography (MRA) in the diagnosis of symptomatic carotid artery stenosis. Methods A total of 88 patients with cerebrovascular diseases diagnosed by digital subtraction angiography (DSA) in our hospital from July 2012 to August 2016 were selected as subjects, and they were divided into the symptomatic group (44 cases) and asymptomatic group (44 cases) according to the type of carotid artery stenosis. Both groups were examined with high-resolution MRA. With the results of DSA as the golden standard, the imaging findings were compared between the two groups. Results The probabilities of plaques in bilateral carotid arteries and internal carotid artery in the symptomatic group were significantly higher than those in the asymptomatic group (P<0.05). A total of 87 carotid arteries stenosis were detected in 44 patients. The numbers of arteries with mild, moderate and severe stenosis detected by DSA were 53, 16, 15 and 3. In the symptomatic group, the numbers of arteries with mild, moderate and severe stenosis and occlusion examined by high-resolution magnetic resonance angiography were 53, 15, 16 and 3, and the accurate rates were 100.00%, 93.75%, 93.33% and 100.00%. Compared the detection rates of DSA, there were no significant differences (P>0.05). Conclusion The accurate rates of high-resolution magnetic resonance angiography are high in the diagnosis of symptomatic carotid artery stenosis and the degree of stenosis. It can be used as the preferred method for diagnosing symptomatic carotid artery stenosis.