Chronic obstructive pulmonary disease (COPD) is a progressive and irreversible airflow limitation with inflammatory response of the lung and airways. COPD is a preventable and treatable disease with some significant extra-pulmonary effects that may contribute to the severity and progress of the disease. Pulmonary Rehabilitation is multidisciplinary intervention helps in improvement of symptoms, decrease of breathlessness, and improves the quality of life. The aim of this study is to estimate and evaluate the effectiveness of PR program in COPD patients. In this study regarding Pulmonary Function Test, there was no statistical significant difference in FEV1 pre and post Rehabilitation, but there was statistical significant difference in (FEV1%F, FVC and FEF) pre and post Rehabilitation. Regarding arterial blood gases there was statistical significant difference in ( PH, Pao2 and O2 mood) ,but there was no statistical significant difference in (Paco2 and Hco3) pre and post Rehabilitation . Regarding 6MWT there was statistical significant difference pre and post Rehabilitation and finally regarding mMRC dysnea scale there was statistical significant difference pre and post Rehabilitation.