Objective The aim of the present study was to investigate oral health‐related quality of life (OHRQoL) and determine associations with demographic, socio‐economic and oral health variables at two evaluation times (2009 and 2015) among older adults assisted by Family Health Units in the Brazil. Methods A longitudinal study was conducted involving the evaluation (2009) and re‐evaluation (2015) of 161 older adults (≥60 years of age). Demographic, socio‐economic and general health variables were collected using a standardised questionnaire. Clinical oral health variables were also collected. OHRQoL was measured using the Oral Health Impact Profile‐14 (OHIP‐14). Multiple regression analysis was employed for the evaluation of OHRQoL considering the variables from the two evaluations. Results The severity of impact (mean OHIP‐14) was 9.12 (SD: 10.81) in 2009 and 8.50 (10.52) in 2015. The greatest impact regarded the psychological discomfort domain at both evaluations (28.8% in 2009 and 22.9% in 2015). In the adjusted multiple linear regression, the mean OHIP‐14 score increased 4.8 points (95% CI: 0.11‐9.49) among individuals who experienced tooth loss between the two evaluations in comparison with those who maintained the same number of teeth. An increase in the OHIP‐14 score occurred between 2009 and 2015 among 40.6% of the older adults. Conclusions The findings of the present study reveal that the oral health status of older adults exerts an influence on OHRQoL, indicating the need for oral health policies directed at this portion of the population.