Abstract Background Evidence suggests that adherence to the Mediterranean diet (MED) may be beneficial in preventing cognitive decline, although findings are inconsistent. We aimed to explore this association in the Czech population of older adults. Methods A total of 6,028 males and females from the Czech arm of the Health Alcohol and Psychosocial factors in Eastern Europe (HAPIEE) study were included in the analysis. Dietary data were collected using a food frequency questionnaire, and MED was calculated based on nine food groups. The MED score ranged from 0 to 16 points and was categorized into three groups: 0-7, 8-10, and 11-16 points. Cognitive function was measured using four tests assessing verbal memory and learning, verbal fluency, and attention, mental speed and concentration, from which single z-scores were computed. The composite score of cognitive function was computed as the mean of z-scores. The cross-sectional associations between MED and composite score of cognitive function were analyzed using multivariate linear regression. Results Females with a dietary score of 8-10 points (Beta=0.05, 95% CI: -0.002; 0.097), and those with a score of 11-16 points (Beta=0.08, 95% CI: 0.016; 0.140) had a higher composite cognitive score than women in lowest adherence group. Looking at specific domains, women in the highest adherence group had significantly better immediate verbal memory (Beta=0.12, 95% CI: 0.031; 0.205) and delayed recall (Beta=0.12, 95% CI: 0.027; 0.212), respectively, than those in the lowest adherence group. There were no associations in males. Conclusions Higher adherence to the MED was associated with better cognitive functioning in verbal memory and composite cognitive score in Czech females. The results suggest that the Mediterranean diet may help to improve cognitive functioning in older women. #NGEU Key messages • Findings suggest that Mediterranean diet may be beneficial in cognitive functioning in older women. • Higher adherence to the Mediterranean diet is connected to better cognitive function particularly in verbal memory domain.