Background: Knee Replacement (KR) results in improved pain symptoms and quality of life, therefore, is one of the most commonly performed orthopedic procedures. The aim of this study was to assess the quality of life among patients with knee replacement. Research design: A descriptive research design was utilized in this study. Setting: This study was conducted at Orthopedic Outpatient Clinic at Benha University Hospital in Benha City. Sample: A convenience sample of patients attended to previously mentioned setting; the total sample included 100 patients. Two tools were used I): A structured interviewing questionnaire which consists of three parts to assess a): Demographic characteristics of patients with knee replacement. b): Medical history of patients with knee replacement 2): Knowledge of patients with knee replacement and 3): Reported practices of patients with KR, II): Quality of life scale to assess the effect KR operation on quality of life among the patients. Results: 52 % of patients with KR aged from 50 years old or more with mean and standard deviation was 50.98±16.55, 64% of the patients had total knee replacement, 26% of the patients had good knowledge about KR, 58% of patients with KR had satisfactory total reported practices scores, and 72% of patients with knee replacement had good total quality of life score. Conclusion: More than one quarter of the patients with KR had good knowledge about KR operation, while more than half of them had satisfactory practices regarding KR and less than three quarters of patients with KR had a good total quality of life scores. Recommendations: Regular follow up for patient with KR to ensure effectiveness of operation, avoiding complication and revision of KR.