Objective To compare Montreal cognitive assessment-basic ( MoCA-B ) and mini-mental state examination (MMSE) in screening cognitive dysfunction of acute stroke patients. Methods The cognitive function of patients (n=83) with acute stroke onset within 10 days (including new cerebral infarction and cerebral hemorrhage) were assessed using MMSE and MoCA-B. The classification of patients with cognitive impairment was compared between the two scales. The consistency of cognitive impairment and affected domains assessed by MMSE or MoCA with experts were evaluated. Results ①There were 32 cases (38.6%) with abnormal MMSE score and 40 cases (51.8%) with abnormal MoCA-B score. ②The the diagnostic consistency of MoCA-B with experts was 89.16%. The false positive of MMSE was 2.41%and the false negative (rate of missed diagnosis) was 16.87%.False positives of MoCA-B were 4.82%and false negatives (rate of missed diagnosis) were 6.02%.③Among the 51 patients with normal MMSE, 15 had abnormal MoCA-B (29.4%). There were significant differences between these two score system in executive function, verbal fluency, directivity, abstraction, delayed recall, visual perception, naming and other cognitive domains (P<0.05). Conclusion MoCA-B scale may be more sensitive and better than MMSE scale in screening for cognitive impairment in patients with acute stroke.