OBJECTIVES: To evaluate the relationship between religiousness and mental health, hospitalization, pain, disability and quality of life in older adults from an outpatient rehabilitation setting in Sao Paulo, Brazil. DESIGN: Cross-sectional study. SUBJECTS/PATIENTS: A total of 110 patients aged 60 years or older were interviewed during attendance at an outpatient rehabilitation service. METHODS: Researchers administered a standardized questionnaire that assessed socio-demographic data, religiousness, self-reported quality of life, anxiety, physical activity limitation, depression, pain and cognition. Predictors were included in each model analysis, and a backward conditional method was used for variable selection using logistic regression (categorical outcomes) or linear regression (continuous outcomes). RESULTS: Thirty-one patients (28.2%) fulfilled criteria for significant depressive symptoms, 27 (24.5%) for anxiety, and 10 (9.6%) for cognitive impairment. Pain was present in 89 (80.7%) patients. Limited depressive symptoms (as assessed by the Geriatric Depression Scale), and greater self-reported quality of life were related to greater self-reported religiousness, as were scores on the Mini-Mental State Examination (less cognitive impairment), and lower ratings of pain. CONCLUSION: Religiousness is related to significantly less depressive symptoms, better quality of life, less cognitive impairment, and less perceived pain. Clinicians should consider taking a spiritual history and ensuring that spiritual needs are addressed among older patients in rehabilitation settings.