BACKGROUND: Optimum management after an acute coronary syndrome (ACS) requires considerable patient engagement/activation. Religious practices permeate people's lives and may influence engagement in their healthcare. Little is known about the relationship between religiosity and patient activation. OBJECTIVE: To examine the association between religiosity and patient activation in hospital survivors of an ACS. DESIGN: Secondary analysis using baseline data from Transitions, Risks, and Actions in Coronary Events: Center for Outcomes Research and Education (TRACE-CORE) Study. PARTICIPANTS: A total of 2067 patients hospitalized for an ACS at six medical centers in Central Massachusetts and Georgia (2011-2013). MAIN MEASURES: Study participants self-reported three items assessing religiosity-strength and comfort from religion, making petition prayers, and awareness of intercessory prayers for health. Patient activation was assessed using the 6-item Patient Activation Measure (PAM-6). Participants were categorized as either having low (levels 1 and 2) or high (levels 3 and 4) activation. RESULTS: The mean age of study participants was 61 years, 33% were women, and 81% were non-Hispanic White. Approximately 85% derived strength and comfort from religion, 61% prayed for their health, and 89% received intercessory prayers for their health. Overall, 58% had low activation. Reports of a great deal (aOR, 2.02; 95% CI, 1.44-2.84), and little/some (aOR, 1.45; 95% CI, 1.07-1.98) strength and comfort from religion were associated with high activation, as were receipt of intercessions (aOR, 1.48; 95% CI, 1.07-2.05). Praying for one's health was associated with low activation (aOR, 0.78; 95% CI, 0.61-0.99). CONCLUSIONS: Most ACS survivors acknowledge religious practices toward their recovery. Strength and comfort from religion and intercessory prayers for health were associated with high patient activation. Petition prayers for health were associated with low activation. Healthcare providers should use knowledge about patient's religiosity to enhance patient engagement in their care.