Background: Chronic Obstructive Pulmonary Disease (COPD) is a global health concern. It is a leading cause of morbidity and mortality worldwide. By 2030 it is predicted to become the third leading cause of death and the sixth cause of disability worldwide. Aim: The study aimed to evaluate the effect of Orem's self-care behavior on quality of life of elderly patients with chronic obstructive pulmonary disease in Benha City. Methods: Quasi-experimental (pre/post-test) design was utilized in this study. The study was conducted at Outpatient Clinics of Chest Hospital in Benha City, Egypt on a purposive sample of 100 elderly patients with chronic obstructive pulmonary disease. A self-administered questionnaire, an observational checklist for elderly patients practicing regarding COPD, Quality of Life Scale (QOLS) and COPD Self-Care Behavior Scale (COPDSC) were used to collect the data. Results: 55% of the studied elderly patients had good total knowledge score post model implementation, 81% of the studied elderly patients were satisfactory practices post model implementation, 72% of the studied elderly  patients had good total quality of life scores post model implementation, also there were improvement in self-care behavior post model implementation p < 0001. Conclusions: This study concluded the positive effects of Orem's self-care behavior on elderly patient's knowledge, practices and their quality of life regarding chronic obstructive pulmonary disease. The study recommended that continuous self -care behavior program for the elderly patients with chronic obstructive pulmonary disease to increase their knowledge and improve their behaviors and their practices.