【Abstract】 Objective To study the relationship between serum miR-181c，miR-21 levels and carotid artery stenosis in patients with cerebral infarction，and to predict the poor prognosis. MethodsIn this study，120 patients with cerebral infarction diagnosed from January 2015 to June 2019 were selected as the research objects，58 patients with carotid artery stenosis，including 24 patients with mild stenosis，22 patients with moderate stenosis，and 12 patients with severe stenosis. The differences of general information，miR-181c and miR-21 levels between carotid stenosis group and non carotid artery stenosis group were compared，and the prognosis was analyzed Risk factors of good patients. ResultsThere was no significant difference in gender，age and body mass index between carotid stenosis group and non carotid stenosis group (P>0.05). The proportion of patients with diabetes mellitus，hypertension and hyperlipidemia in carotid stenosis group were significantly higher than those in non carotid stenosis group (P＜0.05）. There was no significant difference in gender，age，body mass index，hypertension and hyperlipidemia in patients with narrow degree (P>0.05). With the aggravation of carotid artery stenosis，the incidence of diabetes mellitus increased significantly；the levels of miR-181c and miR-21 in patients with carotid stenosis were significantly higher than those in patients without carotid artery stenosis The levels of miR-181c and miR-21 in patients with different carotid stenosis were statistically significant (P<0.05)，and the levels of miR-181c and miR21 were significantly increased with the increase of carotid artery stenosis；the levels of miR-181c (t=6.003，P＜0.05) and miR-21 (t=6.677，P＜0.05) in patients with good prognosis were significantly lower than those in patients with poor prognosis The incidence of urinary disease，hypertension，hyperlipidemia and NIHSS score were significantly higher than those in the good prognosis group；through multivariate analysis，diabetes，hypertension，hyperlipidemia，NIHSS，miR-181c，miR-21 were independent risk factors of poor prognosis. ConclusionThe serum levels of miR-181c and miR-21 increased significantly with the increase of carotid artery stenosis.