Objective: Constipation is a frequent motility disorder and while a common complaint among the overall population, is particularly prevalent among the elderly. The increase of this population group is creating a growing demand for long term care institutions. The present study aims to investigate the prevalence of and factors associated with constipation in elderly residents of long stay care institutions. Method: The study involved 87 individuals. The data collected from each participant included gender, daily intake of water and fiber, physical activity, family history of constipation and nutritional status. The diagnosis of constipation was based on Roma III criteria. Statistical analysis was performed with the SPSS software program (version 18.0) with a level of significance of 5% ( p≤0.05). The Student t, Mann-Whitney, Pearson's chi-square or Fischer's exact tests were employed. Results: The sample was predominantly female (80.5%), with a mean age of 79.4(±9.6) years. A 42.52% prevalence of constipation was observed. Among affected individuals, the condition was more frequent among women (89.2%), those aged over 80 years (67.6%), those who did not engage in physical activity (56.8%), those with below the recommended intake of water and fiber, those who had a family history of constipation, and those who were diagnosed with eutrophia (56.3%). Among the factors analyzed, only age ( p=0.049) and low fiber intake ( p=0.019) were significantly linked to constipation. Conclusion: The results show that constipation is a multifactorial disease that is significantly related to age and low fiber intake.