This study describes the effect of health belief model (HBM) in explaining exercise participation among Jordanian myocardial infarction (MI) patients. A convenient sample of 98 MI patients was recruited from four governmental hospitals in northern Jordan. A self-reported questionnaire and structured interview were designed to obtain the needed information. Study results indicated that Jordanian MI patients had a high score in perceived severity and a low score in perceived barriers. Results also showed a significant correlation between exercise participation and health belief variables and sociodemographics such as age, annual income, level of education, and physician recommendation. These findings have implications for designing intervention programs aimed at improving physical activity by all MI patients. These programs should consider culture, socioeconomic status, personal system, and demographics. Further research is needed to develop a culturally sensitive instrument that takes into consideration the cultural variation and the specific needs of MI patients.