Abstract: OBJECTIVE To observe the clinical effect and safety of combination of sildenafil and atorvastin or beraprost on pulmonary arterial hypertension (PAH). METHODS Fifty-four patients with PAH were randomly divided into two groups and were given treatment with combination of sildenafil and atorvastin or combination of sildenafil and beraprost respectively. 6-Minute walk distance (6MWD), mean pulmonary artery pressure (mPAP), pulmonary vascular resistance (PVR) and cardiac index (CI) were observed after six months. RESULTS Two groups could both increase 6WMD, decrease mPAP and PVR and improve CI. The effect in the group given with combination of sildenafil and beraprost was more significant. There was no significant side-effect and severe adverse reaction in every group. CONCLUSION The effect of combination of sildenafil and beraprost is more significant than the combination of sildenafil and atorvastin on PAH. The combination of sildenafil and beraprost is safe and effective in treating PAH.