BACKGROUND Deep vein thrombosis (DVT) and pulmonary embolism (PE) are conditions with significant morbidity and mortality. Proximal DVT has a significant association with PE and possible fatal outcomes. Traditionally, PE is subdivided into symptomatic PE and asymptomatic PE, which have different treatments, preventions and prognoses. The growing utilization of computed tomography pulmonary angiography has led to increased detection of PE in DVT patients. This study examined the clinical characteristics and compared symptomatic PE and asymptomatic PE following proximal DVT. METHODS: The medical records of 258 DVT inpatients from July, 2012 to June, 2015 were reviewed retrospectively. After excluding the patients who did not performed PE evaluation and were not diagnosed with PE, 95 patients diagnosed with PE following proximal DVT were enrolled in this study. They were divided into the symptomatic PE group and asymptomatic PE group. RESULTS: The body weight, body mass index, thrombus size, thrombus length and location were similar in the two groups. The symptomatic PE following proximal DVT group showed an older age, higher incidence of emergency department access (85.0% vs. 38.7%, p < 0.001) and preceding infection (25.0% vs. 1.3%, p < 0.001) as well as a higher incidence of immobilization (45.0% vs 13.3%, p=0.016). In the multivariate logistic regression study, preceding infection and emergency department access showed significant association with symptomatic PE. CONCLUSION: In proximal DVT inpatients, symptomatic PE was associated with emergency department access and preceding infection. The possibility of a symptomatic PE event should be considered in proximal DVT patients, especially those who were admitted through the emergency department and had preceding infection.