Background: L-asparaginase (L-asp)-associated venous thromboembolism (VTE) is a serious adverse complication associated with acute lymphoblastic leukemia (ALL) and lymphoma treatment. The incidence rate of L-asp-related VTE in Asian cancer patients is not well known. Methods: We performed a population-based study between 2009 and 2013 using claim databases, including both diagnostic and medication codes, such as anti-cancer treatment with L-asp and VTE diagnoses from the starting date until 3 months after cessation of L-asp. Results: A total of 3286 patients were prescribed L-asp treatment for any type of lymphoid malignancy including ALL and lymphoma; 116 patients (3.5%) experienced VTE. The most common site of thrombosis was the upper extremities (34.5%). Cerebral vein thrombosis (1.7%) occurred in two pediatric patients; 2.4% (43/1795) of pediatric patients and 4.9% (72/1486) of adult patients suffered from VTE, respectively; 2.7% (56/2064) of ALL and 4.9% (59/1217) of lymphoma patients were diagnosed with VTE after L-asp exposure. After univariate analysis, both the diagnosis of lymphoma (vs. ALL) and being an adult patient (vs. pediatric patient) were risk factors for VTE occurrence. However, after multivariate analysis, only age >18 remained a risk factor for VTE (odds ratio, 1.79; 95% confidence interval, 1.14-2.81). Conclusions: This is the first and largest population-based study in Asian patients with lymphoid malignancies treated with L-asp demonstrating that adult patients are at elevated risk of thrombosis after L-asp exposure. The overall incidence of L-asp-related VTE amongst these patients was similar to that in Caucasian populations.