Background: Knee arthroscopy is a surgical procedure utilized for the diagnosis and treatment of knee joint in the elderly to enhancing longevity, activity levels, and overall health. Aim: To evaluate the effect of psycho educational program on the negative mood, hope level and quality of life of elderly patients’ undergoing knee arthroscopy.  Design: A quasi-experimental research design was used in this study. Sitting: The research was conducted in the orthopedic department and the arthroscopic unit at Main Assiut University Hospital. Sample: Seventy-four male and female elderly patients who were scheduled to underwent knee arthroscopy were included in this study after they were randomly divided into the study and control groups, (37) patients each. Tools: (I): Structured elderly Interview Questionnaire Sheet, (II): Negative mood scale: (III): Herth Hope Index (HHI) & (IV): Medical Outcomes Study 12-Item Short-Form (MOS SF-12). Results: The study group exhibited significantly higher scores in hope level and quality of life compared to the control group (P<0.001).  The study group exhibited a lower negative mood score compared to the control group (P<0.001) following the implementation of the psychoeducational program. Conclusions: The implementation of the psychoeducational program has statistically significant improvements in negative mood, hope levels, and quality of life among elderly patients undergoing knee arthroscopy, which positively influence patient outcomes.  Recommendation:  Preparation for elderly patients prior to knee arthroscopy is a crucial step in enhancing hope, reducing negative mood, and improving overall quality …