Background: Adjustment of life style required multifactor as education, physical exercise, healthy diet, and pharmacological strategies which considered an imperative guidelines for treatment and prevention of metabolic syndrome. Aim: investigate the effectiveness of nurse-led lifestyle intervention on outcomes of metabolic syndrome patients. Method: A quasi-experimental research, a convenience sample of 160 patients attended to medical and diabetic out-patients clinics of Specialized Medical Hospital, Mansoura University. An interview questionnaire was used to accomplish this study. Results: High percentages of the studied groups pre-test were low self-efficiency (≤ 37.6), while high percentages of the studied groups post-test were having high self efficiency (≥ 74.6). There were statistical significant correlation between metabolic syndrome and health-promoting lifestyle and self-efficiency among studied patients (P. value 0.01). Conclusion: Applying the nurse-led lifestyle applied program has positive effect on promoting self-efficacy and health promoting behaviors for metabolic syndrome patients. Recommendations: It is important to ensure application of lifestyle applied program by nurses as a scheduled care for metabolic syndrome patients.