INTRODUCTION: No data are available on the association between adherence to the Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) diet and breast cancer. MATERIALS AND METHODS: This population-based case-control study was conducted among women aged ≥ 30 years, who were residing in Isfahan, Iran. The study included 350 patients with newly diagnosed stage I to IV breast cancer, for whom in situ or invasive status of breast cancer was confirmed by physical examination, mammography, and pathologic verification. Controls were 700 age-matched apparently healthy individuals who were randomly selected from the general population. Dietary data were collected using a validated 106-item Willett-format, semi-quantitative dish-based food frequency questionnaire. RESULTS: After adjustment for age and energy intake, women in the top tertile of the MIND diet score had 60% lower odds of breast cancer than women in the bottom tertile (odds ratio [OR], 0.40; 95% confidence interval [CI], 0.29-0.55). In the fully adjusted model including body mass index, those with the greatest MIND diet scores had 50% lower chance of breast cancer (OR, 0.50; 95% CI, 0.34-0.72) than those with the lowest adherence to the MIND diet. Postmenopausal women with the greatest adherence to the MIND diet were less likely to have breast cancer than those in the bottom tertile (OR, 0.45; 95% CI, 0.30-0.66). In addition, we found a significant inverse association between adherence to the MIND diet and odds of breast cancer among normal-weight women (OR, 0.39; 95% CI, 0.25-0.60). CONCLUSION: Adherence to the MIND diet was associated with a reduced chance of breast cancer in this case-control study.