Background: Acute pulmonary thromboembolism(APTE) remains an important cause of morbidity and mortality in Western countries.In Korea, both the incidence and the mortality rate of APTE were thought to be low compared to Western countries. We performed the present study to investigate the current status of APTE in Korea. Methods: Eight hundred and eight registry patients with APTE were analyzed with respect to clinical symptoms and signs, the presence of underlying diseases or predisposing factors, diagnostic methods, treatment and clinical course. Results: The most common risk factors were prolonged immobilization(22.9% ), deep venous thrombosis(22.0% ), a recent operation(19.2% ), and cancer(15.8% ). The most common symptoms were dyspnea(78.6% ), and chest pain(26.9% ). The most common abnormality on chest radiography was effusion. The overall mortality rate at 3 months was 11.0% . Multivariate logistic regression analysis demonstrated that increased mortality risk was independently associated with the following baseline factors: onset in hospital(OR 1.88; 95% CI 1.03-3.42; p=0.03), lung cancer(OR 9.20; 95% CI 1.96-43.27; p=0.005), tachycardia(OR 3.50; 95% CI 1.86-6.60; p=0.0001), cardiogenic shock(OR 6.74; 95% CI 2.73-16.64; p=0.0001), and cyanosis(OR 3.45; 95% CI 1.27-9.44; p=0.01). Conclusions: Some differences did exist for the risk factors, symptoms, chest X-ray findings, mortality rate and prognostic factors as compared with those for Western patients. These results can prove especially helpful in the diagnosis as well as for the treatment of patients with APTE. Background: Acute pulmonary thromboembolism (APTE) remains an important cause of morbidity and mortality in Western countries.In Korea, both the incidence and the mortality rate of APTE were thought to be low compared to Western countries. We performed the present study to investigate the current status of APTE in Korea. Methods: Eight hundred and eight registry patients with APTE were analyzed with respect to clinical symptoms and signs, the presence of underlying diseases or predisposing factors, diagnostic methods, treatment and clinical course. Results: The most common risk Factors were prolonged immobilization (22.9%), deep venous thrombosis (22.0%), a recent operation (19.2%), and cancer (15.8%). The most common symptoms were dyspnea The most common abnormality on chest radiography was effusion. The overall mortality rate at 3 months was 11.0%. Multivariate logistic regression analysis demonstrated that increased mortality risk was independently a The results of the study were as follows: ssociated with the following baseline factors: onset in hospital (OR 1.88; 95% CI 1.03-3.42; p = 0.03), lung cancer (OR 9.20; 95% CI 1.96-43.27; p = 0.005) % CI 1.86-6.60; p = 0.0001), cardiogenic shock (OR 6.74; 95% CI 2.73-16.64; p = 0.0001), and cyanosis (OR 3.45; 95% CI 1.27-9.44; p = 0.01) differences did exist for the risk factors, symptoms, chest X-ray findings, mortality rate and prognostic factors as compared with those for Western patients. These results can be particularly helpful in the diagnosis as well as for the treatment of patients with APTE.