Background Total hip replacement surgery has become the treatment of choice for patients suffering from rheumatoid arthritis and osteoarthritis of the hip. The Aim of the study: assess the effect of rehabilitation regimes on improving function outcome for patients undergoing total hip replacement surgery. Research design: A quasi-experimental design had utilized in this study. Study setting this study was carried out in the Orthopedic Departments at main Mansoura university hospital. Subjects Purposive sample including all available patients who admitted to the orthopedic department during six months and treated with total hip replacement (66 patient), and divided into two groups study and control group study tools: Two tools were utilized. Tool (1) Patients Adjustment Tool: This tool was used to measure the effects of the applied regimes on patients' post-hospital functional outcome after total hip replacement. It contains 6 parts (2) The Rehabilitation Program: This program planned to cover knowledge and practice for total hip replacement patients aiming to improve their functional outcome. Results: It can be noticed that the mean age of subjects was 41 years for the study group and 46 years for the control groups. In relation to sex Females, patients represented the higher percentage (60%) and (63%) for both the study and control groups respectively. It was found that there was a significant difference between study and control groups in relation to a post-discharge period (p <0.001*). Also, it showed a significant difference between preoperative and post-discharge function outcome in the study and control groups Paired t-test (P value) < 0.001*< 0.001*. Conclusion: the rehabilitation program that implemented to study group patients had a positive effect on functional outcome. Recommendations: rehabilitation program should be started on the first day of patient admission to hospital, a Simple booklet written in the Arabic language should be available for all patients undergoing total hip replacement.