Background: Echocardiography is readily available noninvasive technique that can be used to asses pulmonary artery pressure in chronic obstructive pulmonary disease (COPD). Objective:  Evaluation of the role of echocardiography in diagnosis and assessment of pulmonary hypertension (PH) in COPD patients in different stages of severity, stable condition and in exacerbation. Patients and methods: This study included 80 patients with COPD admitted in chest department of Al-Azhar University Hospital (Damietta), during the period from June 2011 to June 2013. Patients were divided into four equal groups. The first group included those with stable COPD; the second group included patients with COPD exacerbation; the third group included cigarette smokers without manifestations of COPD; and the fourth group included healthy non-smokers. All subjects of the present work were exposed to full history taking, detailed clinical examination and laboratory investigations (arterial blood gases, chest X-ray, electrocardiogram, pulmonary function tests, spirometry (FEV1, FVC, FEV1/ FVC%) and Doppler echocardiography. Results: No significant difference between groups as regard to age, while there was significant increase of smoking in COPD cases when compared to healthy controls. There were significant increase of smoking in both groups A and B when compared to group C.  In addition, there were significant increase of peak tricuspid jet velocity; intermediate tricuspid jet velocity and right atrium pressure in group B and group (A) when compared to group C and group D. Similarly, there were significant increase of calculated pulmonary arterial pressure in groups B and A when compared to groups C and D. The overall prevalence of pulmonary arterial pressure (PAP) in COPD cases was 65.0% with significant increase of both prevalence and severity of PAP in group B when compared to group A. There were significant, inverse correlations between pulmonary artery pressure on one side and both SaO2, PaO2, and FEV1/FVC the other side. On the other hand, there was significant positive correlations between PAP from one side, and PaCO2, hemoglobin concentration, WBCs, peak intermediate tricuspid jet velocity and right atrium pressure on the other side.  Conclusion: The results of the present study showed an association of pulmonary hypertension in 65% of COPD cases, and this reflected impact of clinical, physiologic and pathologic changes of the disease on PAP. It is advisable to screen all COPD patients for pulmonary hypertension (PH) using ECHO and to control pulmonary artery pressure in those cases as a line of treatment of COPD itself.