Abstract: Objective To investigate the diagnosis and treatment of pulmonary arter ial hypertension (PAH) associated with paradoxical embolism (PDE). Methods Clinical data about 418 patients admitted to Beijing Universi ty of Chinese Medicine Affiliated Huguosi Chinese Medicine Hospital were retrospective ly summarized and the patients were divided into PAH not associated with PDE group (n=350) and PAH combined PDE group (n =68) according to the doppler echocardiography and/or right angiography. General data, the differences between mortality an d the doctor-patient contradiction complaint were compared in t wo groups. Results The occurrence of autoimmune diseases, chronic obstructive pul monary disease (COPD), pulmonary embolism and dead cases in PAH combined PDE group were significantly hig her than that in PAH not associated with PDE group (P＜ 0.05). Conclusion PAH combined PDE are easily ignored by clinical treatment and lacking of foresight, paradoxical embolism should be taken into consideration when systemic arterial embolism with u nknown causes appears.