PURPOSE: Psychoeducation is a recommended component of cardiac rehabilitation, but to date, evidence from high quality trials examining behavior change has not been synthesized. The primary aim of this systematic review was to examine the effectiveness of psychoeducation on behavior change in adults with coronary artery disease participating in cardiac rehabilitation; and to identify if changes in health behavior had an effect on modifiable physiological risk factors. METHODS: A search of electronic databases was conducted for randomized controlled trials involving adults with a primary diagnosis of myocardial infarction, coronary artery bypass graft surgery, percutaneous coronary intervention, stable angina, or coronary artery disease defined by angiography. Trials comparing psychoeducational programs to exercise only, standard cardiac rehabilitation or medical care were included. Primary outcomes were smoking status, physical activity, dietary habits, supplemental oxygen, or medication use. Included trials were assessed for quality with the PEDro scale, and data synthesized descriptively or with meta-analysis. RESULTS: Six randomized controlled trials and 1 quasiexperimental trial were included, a total of 536 participants. A meta-analysis from 213 participants showed psychoeducational interventions produced a significant positive effect on physical activity levels over the medium term (6-12 months) when compared with exercise and risk factor education, (δ = .62, 95% CI 0.3-0.94). However, there was limited positive evidence for change in smoking and dietary behavior. No effect was found on physiological risk factors. CONCLUSIONS: Psychoeducational interventions produce a significant positive effect on physical activity levels and potentially on dietary habits and smoking. Strategies such as goal setting, problem solving, self-monitoring, and role modeling appear to be influential in this change.