Background: Myocardial infarction (MI) is a fatal disease characterized by the development of localized necrotic areas within the myocardium. Self-care in MI is an essential element in improving quality of life. Aim: To evaluate the effect of self-care training on knowledge in patients with myocardial infarction. Subjects and Method: Design: A quasi-experimental research design was utilized. Subjects: A purposive sample of 120 adult patients was recruited. Tools: Structured interview questionnaire was used to gather data consisted of (demographic characteristics and health relevant data sheet and patients' knowledge assessment questionnaire).Results: There was a statistically significant difference between studied groups in relation to knowledge domains, as study groups show significant improvement in knowledge level (p < 0. 001) compared to the control group in all domains Conclusion: Knowledge of the study group improved significantly after self-care training module compared to the control. Recommendation: Continuous patient education through audio-visual materials and follow-up of patient outcomes.