Background: Chronic obstructive pulmonary disease (COPD) is a progressive disease characterized by increasing airflow limitation and respiratory symptoms, often associated with chronic co morbidities, leading to a significant burden for the patient. Aim of the work: to assess plasma NT-proBNP level in patients with acute exacerbation of COPD (AECOPD) and to evaluate the prognostic value of elevated NT-proBNP levels to predict in-hospital outcome of those patients. Material and Methods: From 1 November 2010 to 30 April 2011, 45 adult patients ≥ 40 years of age with acute exacerbation of COPD (AECOPD) admitted to department of pulmonary medicine &or Respiratory ICU ;Assiut University Hospital; Egypt were enrolled in this study. Plasma NT-proBNP levels were measured and systolic pulmonary arterial pressure (SPAP) was estimated by echocardiography. Arterial blood gas analysis, forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1) were also measured. Results: NT-proBNP levels were significantly elevated during the acute exacerbation compared to recovery (254 pg/mL [interquartile range IQR, 103 to 972 pg/mL] vs 89 pg/mL [IQR, 45 to 269 pg/mL]; p = 0.000). Also in those patients requiring ICU admission [416 pg/mL (IQR, 214 to 972)] vs [200.5 pg/mL (IQR,103 to 516)]p=0.000.To predict ICU admission in patients with AECOPD, a receiver operating Characteristic (ROC) analysis was performed with NT-proBNP level > 300 has the best sensitivity and specificity (Sensitivity = 89.5%, Specificity = 92.3%) with area under the ROC curve (AUC) = 0.933. NT-proBNP levels at exacerbation were significantly elevated in patients with cor pulmonale compared to those without cor pulmonale [329 pg/mL (IQR, 167 to 972)] vs [197pg/mL (IQR,103 to 324)]p=0.000. With cut-off level of NT-proBNP > 214 pg/ml, which gives the best sensitivity and specificity (Sensitivity = 95.7%, Specificity = 72.7%) with area under the ROC curve (AUC) = 0.895. There was significant correlation between NT-proBNP levels at exacerbation and partial pressure of carbon dioxide (PaCO2),(PH),systolic pulmonary artery pressure(SPAP),duration in ICU and length of hospital stay (r =-0.422, p =0.004) , (r =-0.426, p =0.004) , (r = 0.811, p =0.000) , (r = 0.765, p =0.000) and (r = 0.805, p =0.000) respectively. Conclusions: This study revealed that, plasma NT-proBNP levels are elevated in AECOPD patients and can predict the need for ICU admission. Also can predict the occurrence of cor pulmonale in those patients.