AIM: To determine the prevalence of cognitive impairment and to examine the correlation between demographic and social factors, the activities of daily living (ADL), and depression with cognitive function in elderly Mexicans living in nursing homes. DESIGN: Cross-sectional. SETTING: Fourteen nursing homes in Guadalajara. PARTICIPANTS: Data were drawn from a random sample of 451 elderly, aged 60-104 years. MEASUREMENTS: The Spanish versions of MMSE (Folstein). ADL index (Barthel), and the Geriatric Depression Screening (GDS) (Yesavage); demographic factors were obtained. RESULTS: The prevalence of cognitive impairment was 52.3%, with a cut-off of 19/20 (Bohnstedt). Cognitive impairment was significantly related to gender, educational level, activity participation, pension, ADL, and depression. CONCLUSION: The results indicate a higher prevalence of cognitive impairment than in other Mexican studies. The data are consistent with previous findings that cognitive impairment in the elderly is more common among females, those with a low level of education, the lack of participation in social/leisure activities, ADL dependencies, and depression