The studies on the prevalence of dementia, depression, and mild cognitive impairment (MCI) in Greece are sparse and show major variations of prevalence depending on geographical areas, nutritional habits, and the way of living. The aim of this door-to-door study was to find the prevalence of dementia, depression, and MCI in a rural Greek population. Four hundred and forty-three individuals older than 61years following the application of specific criteria were diagnosed with: normal cognition, depression, MCI with and without depression, and dementia with and without depression. Four diagnostic methods were used, 2 of which included Mungas correction for age and education. After Mungas adjustment, the results were as follows—depression: 33.9%; MCI: 15.3%; MCI with depression: 8.6%; dementia: 2.0%; and dementia with depression: 7.2%. Dementia is less prevalent compared to global data and other Greek areas. Mild cognitive impairment is more prevalent than dementia. High percentages of depression may be related to low education.