Objective:To estimate the relationship between inflammation and pulmonary hypertension in patients with chronic obstructive pulmonary disease,we investigate the levels of C-reactive protein (CRP)and interleukin-6 (IL-6)in serum and exhaled breath condensate (EBC)in chronic obstructive pulmonary disease (COPD)with or without pulmonary hypertension. Methods:EBC and serum of 37 cases in PH associated with COPD and 48 cases in single COPD were collected. Lung function,arterial blood gases and echocardiography were assayed in all cases. ELISA was used for detecting the levels of IL-6 in EBC and serum. Particle-enhanced turbidimetric immunoassay was used for analyses the levels of hs-CRP in EBC and serum. Results: ①The levels of CRP[(17.16 ± 6.25)mg/L]and IL-6[(79.67 ± 18.72)ng/L]in serum in patients with pulmonary hypertension were significantly higher than those in patients without pulmonary hypertension (P < 0.001). ②The levels of CRP[(2.03 ± 0.46)mg/L mg/L]and IL-6[(8.75 ± 2.03)ng/L]in EBC in patients with pulmonary hypertension were significantly higher than those in patients without pulmonary hypertension (P < 0.05). ③PASP in the PH group was positively correlated with the levels of CRP and IL-6 both in serum and EBC(r = 0.415~0.875,P < 0.001). Conclusion: The inflammation reaction of system and local respirary tracts plays an important role in the pathogenisis of pulmonary hypertension in COPD.