Background/Aims: Almost half of community-dwelling patients and 59.6% of institutionalized residents with dementia are in moderate or severe stages of this disease. The Mini-Mental State Examination (MMSE) has limited applicability to these patients due to floor effects. We aimed to determine the correlation between the MMSE and the Severe Mini-Mental State Examination (SMMSE), as well as SMMSE association with functional scales in patients having moderate to severe dementia and low levels of education. Methods: A cross-sectional study of patients 60 years or older attending an outpatient clinic was conducted. The MMSE, SMMSE and functional scales were applied. Clinical and demographic data from medical records were reviewed. Results: Seventy-five patients with a mean of 4.1 ± 3.6 years of education were analyzed. The mean scores on the MMSE and SMMSE were 7.8 ± 7.0 and 17.8 ± 9.4, respectively. The results indicated that the MMSE and SMMSE correlated only in patients who had an MMSE score of less than 10 (r = 0.87; p < 0.001). In addition, significant correlations were found between the SMMSE and functional scales (p < 0.001). It was observed that educational level did not interact with SMMSE performance. Conclusion: The SMMSE is a useful and reliable tool for a brief cognitive assessment of advanced dementia patients with low educational levels.