Some studies suggest that religiosity may be related to health outcomes. The current investigation, involving 92,395 Women's Health Initiative Observational Study participants, examined the prospective association of religious affiliation, religious service attendance, and strength and comfort from religion with subsequent cardiovascular outcomes and death. Baseline characteristics and responses to religiosity questions were collected at enrollment. Women were followed for an average of 7.7 years and outcomes were judged by physician adjudicators. Cox proportional regression models were run to obtain hazard ratios (HR) of religiosity variables and coronary heart disease (CHD) and death. After controlling for demographic, socioeconomic, and prior health variables, self-report of religious affiliation, frequent religious service attendance, and religious strength and comfort were associated with reduced risk of all-cause mortality [HR for religious affiliation = 0.84; 95% confidence interval (CI): 0.75-0.93] [HR for service attendance = 0.80; CI: 0.73-0.87] [HR for strength and comfort = 0.89; CI: 0.82-0.98]. However, these religion-related variables were not associated with reduced risk of CHD morbidity and mortality. In fact, self-report of religiosity was associated with increased risk of this outcome in some models. In conclusion, although self-report measures of religiosity were not associated with reduced risk of CHD morbidity and mortality, these measures were associated with reduced risk of all-cause mortality.