Objective: Determine the proportion of patients COPD with heart failure and study thems clinical, paraclinical characteristics. Subjects: patients diagnosed determind COPD, following GOLD 2011 criteria, hospitalized in the Respiratory Departement of Viet-Tiep Hospital from 6/2012 - 8/2012. Methode: Prospective, cross-sectional and descriptive study. Results: 122 patients COPD which 41 percent has heart failure (right 33 percent, 7 percent left, 1 percent total). Characteristics of patient's COPD with the heart failure: women with age 50-69, onset hospitalised time 7 days, or = 2 decompensations/year, history hospitalised in reanimation, hypertension, rale wet in pulmonary bottoms, image interstitial pulmonary, chest cardiac index 50 percent on Xray, distribution in group D, has respiratory acidosis decompensation and treated with assisted ventilation in acute respiratory failure. Conclusions: Heart failure is a serious prognostic factor in patients COPD, so when clinical symptoms suggested to do an echocardiogram (Doppler) for the early detection, accurate diagnosis of heart failure. It is necessary for coordination of treatment among pulmonary and cardionary specialists.