OBJECTIVE To observe the long-term effect of nifedipine (control release tablets) in patients with chronic obstructive pulmonary disease and cor pulmonale. METHODS A randomized, double blind, placebo-controlled design was made, two hundred and two patients (FEV1/FVC was 47.35% +/- 8.10%) were divided into two groups: nifedipine group (20 mg Bid) 102 cases, placebo group (one tablet Bid) 100 cases. RESULTS The equilibrium test between both groups was comparable. Two-year follow-up rates of both groups were 94% and 89%, respectively. The comparision of the nifedipine to placebo group was as follows: in nifedipine group, the improvement of dyspnea, fatigue and exercise capacity showed significantly better results (P < 0.05); FEV1 and PaCO2 deterioration was unremarkable (P > 0.05); the pulmonary impedance plethysmogram B-Y1 that reflects pulmonary vascular compliance appeared significant improvement (P < 0.05) and the mortality of the disease that was the most important observation endpoint was declined (P = 0.051), but some electrocardiographic index reflected right ventricular load became worse (P < 0.05). CONCLUSIONS Long-term taking controlled release-nifedipine is a safe, effective measure which might improve life quality and decrease mortality in patients with chronic obstructive pulmonary disease and chronic cor pulmonale, however the drug can not slow down or reverse the progress of this illness.