OBJECTIVES: Venous thromboembolism (VTE) is a common complication among cancer patients which results in significant morbidity and mortality. Although the need to optimize the prevention of VTE has been recognized in Western countries, the understanding of the epidemiology of VTE in Asian countries remains limited. The goal of this population-based observational study is to explore the epidemiology and clinical profiles of VTE among cancer patients in Taiwan  METHODS: Using Taiwan’s National Health Insurance Research Database, we identified newly diagnosed cancer patients between 2001 and 2010. Study outcome was defined as a hospitalization with VTE diagnosis during or after the cancer diagnosis date. To verify the accuracy of VTE diagnosis, patients must have received subcutaneous or intravenous anticoagulants, surgical thromboectomy, angioplasty or insertion of inferior vena cava filter during the VTE hospitalization. The incidence rate of VTE for the entire study cohort and subgroups of patients categorized by sites of cancer was estimated. RESULTS: Among 46,061 cancer patients, 555 (2.7 per 1000 patient-year) patients had VTE admission (438 (78.92%) venous thrombosis, 91 (16.40%) pulmonary embolism (PE) and 26 (4.68%) with concomitant PE and venous thrombosis) during or after the cancer diagnosis date. Sites of cancer with the highest rates of VTE were myeloma, pancreas, liver, lung, and ovary, with incidence rates were 5.52, 5.49, 4.67, 4.53, and 4.42 per 1000 patient-year, respectively. Approximately one-fifth (19.46%, n=108) of VTE admission was occurred at the cancer diagnosis date. Cumulative occurrence of VTE within 1, 3, 6, and 12 months were 26.49%, 40.18%, 49.01%, and 59.28%, respectively. CONCLUSIONS: Although the incidence of cancer-related VTE among Taiwanese is lower than Caucasians population, it is not rare in specific cancer such as myeloma, pancreas and liver cancer. Most VTE occurred within 1 year after cancer diagnosis. Prevention of VTE may be optimized in higher-risk patients.