Despite the well-documented benefits of exercise, adherence among patients with coronary heart disease (CHD) has been low during and after cardiac rehabilitation (CR) as well as among patients not attending CR. Therefore, an understanding of the factors that influence exercise in this population is crucial to assist in the development of effective interventions. The goal of this review was to document the correlates of exercise of CHD patients in all CR contexts from a social-ecological perspective that addresses multiple levels of influence on exercise. The search strategy included PubMed, PsychINFO and Web of Science databases. In all, 121 studies, examining 32 different correlates of exercise, with a total of 25 217 participants were included. Across all CR contexts, six variables were consistently related to exercise (self-regulatory self-efficacy, health status, intention, perceived control, beliefs/benefits and previous physical activity). Several variables were also related to exercise in three of four contexts (e.g. task self-efficacy, perceived barriers, attitude, action planning, sex and employment status). Many of the variables consistently related to exercise may be amenable to change through the development and implementation of appropriate interventions. Specific suggestions are made for each relevant variable to assist CR staff and other healthcare practitioners in 32 promoting exercise among CHD patients. Current gaps in literature such as a lack of prospective studies and research examining broader (e.g. policy level) correlates are also discussed.