Background: Pulmonary hypertension is the major cardiac complication of chronic obstructive pulmonary diseases (COPD). Also it is considered as a predictor of mortality independent of the pulmonary obstruction severity. Due to different methods of diagnosis and lack of the gold standard Right heart catheterization (RHC), diagnosis of PH in COPD patients could be missed and hence its treatment may be deficient which could impair the quality of life and lead to poor prognosis. So the aim of this work is to detect the frequency of pulmonary hypertension (PH) among stable COPD patients, and to evaluate the possible correlation of PH with the severity of the disease. Patients and methods: This study included 84 stable (COPD) patients with different grades of severity. All patients were subjected to Spirometric Pulmonary function test (PFTs), Electrocardiography (ECG) and Echocardiogram (ECHO). RHC was performed to mild and moderate COPD patients with severe PH diagnosed by Echocardiography. Results: PH was found among 33(39.3%) COPD patients; 17 (51.5%), 4 (12.1%) and 12(36.4%) were having mild, moderate and severe PH respectively as diagnosed by ECHO. Out of proportion PH was present in 3 cases only with mild COPD, and 4 cases with moderate COPD. A positive correlation was observed between echocardiography and RHC regarding measurement of mPAP (mmHg) with statistically significant difference (p < .05). Conclusion: 1-Pulmonary hypertension is a common sequel in COPD patients mostly with moderate severity, and is mainly of mild degree of PH. 2-Small proportion of COPD patients could develop PH disproportionate to the degree of airway obstruction which termed as out of proportion PH. 3-ECHO and even RHC are of crucial importance in detection of PH in patients with COPD in order not to miss cases with out of proportion PH.