The objective of the review was to assess the relationship between insulin resistance and cognitive impairment. Medline, Embase, Web of Science and Cochrane Library were searched. Two independent authors selected studies and extracted data. Quality of included studies was assessed by NOS (Newcastle-Ottawa quality assessment scale). A random-effects model with its 95% confidence intervals (CIs) was considered for meta-analysis. Eight articles including 1,399 subjects were included in this meta-analysis. The article showed a negative association between insulin resistance and cognition (R = - 0.262; 95% CI-0.309, - 0.215). There is evidence that insulin resistance may be a mechanism of cognitive impairment. Key Words: Insulin resistance, Insulin, Cognition, Cognitive impairment, Systematic review, Alzheimer's disease.