Few population-based studies have examined long term cognitive trajectory, and these studies were conducted in high income countries. We investigated the association of age, gender and education with 10-year cognitive trajectory in a well-defined population of elderly using data from the Bambuí Cohort Study of Aging, in Brazil. Cognition was measured using the Mini- Mental State Examination (MMSE). Cohort members underwent annual follow-ups. This analysis was based on 12,206 MMSE measurements from 1,461 (91%) baseline participants. We used mixed effects models to study MMSE as outcome. The key findings from this analysis are that women and people with a higher schooling level at baseline had high scores of MMSE, while older participants started off lower. Regarding cognitive decline, women, older people and those with a higher schooling level declined faster.