This study presents a systematic review on existing cognitive screening tools for mild cognitive impairment and dementia in populations with low education and literacy levels. Cochrane Library, PubMed and LILACS databases were examined for studies including adults aged 50 years old or older with low educational level. 61 articles were included. Despite its frequent use, studies on Mini-Mental State Examination (MMSE) revealed that educational level biased the score obtained, regardless of other factors. Separately, the Informant Questionnaire on Cognitive Decline in the Elderly, the Fototest, or the Eurotest, appear to minimize the effect of education and literacy. MMSE is unreliable for individuals with low literacy. Tasks involving reading, writing, arithmetics, drawing, praxis, visuospatial, and visuoconstructive skills have a greater educational bias than naming, orientation, or memory. An adequate determination of educational level and validation of instruments in populations with heterogeneous levels of literacy requires further research.