Background: liver transplantation is a widely accepted therapeutic modality for individuals experiencing complications due to end-stage chronic liver disease. Aim: The study aimed to evaluate the effect of an instructional program on promoting a healthy lifestyle among patients post liver transplantation. Study design: A quasi experimental design was used. Setting: Out-patient clinic for post-transplantation follow-up at Ain Shams Specialized Hospital. Sample: A purposive sample included 90 post- liver transplantation patients. Tools: The first tool: A structured interview questionnaire consisting of four parts was used. Part I: To assess demographic data of patients after post liver transplantation, Part II: To assess Patients` history, Part III: to assess patients' knowledge regarding post liver transplantation. Second tool: To assess the health-promoting behaviour level of patients. Results: The study concluded 90 patients post liver transplantation participated in this study. Significant improvements were observed in patients' health-promoting lifestyle behaviors from pre-program phase to post-program and follow-up stages. Scores increased from 8.07±5.13 to 31.60±4.74 and further to 40.20±3.84, emphasizing the effectiveness of the instructional program. Conclusion: The study concluded that the program positively impacted patients' knowledge and their health-promoting lifestyle behavior regarding post liver transplantation. Recommendation: Establishing a comprehensive nursing discharge plan that incorporates education on self-care knowledge, lifestyle modifications and various treatments at home.