Context Patients with aggressive lymphomas are at higher risk for venous thromboembolism (VTE). ThroLy is a risk assessment model (RAM) derived to predict the occurrence of VTE in various types of lymphomas. Objective In this study, we assess the clinical application of ThroLy RAM in a unified group of patients with diffuse large B-cell lymphoma (DLBCL). Design A retrospective study. Items in the ThroLy RAM, including prior VTE, reduced mobility, obesity, extranodal disease, mediastinal involvement, neutropenia, and hemoglobin Patients Hospital databases were searched for patients with DLBL and radiologically confirmed VTE. A total of 524 patients, median age 49 (range: 18–90) years, were included. Of these patients, 52.3% were males, 30.7% were obese, and 26.5% were active smokers. Patients had high disease burden: 57.3% with stage III/IV, and 34.0% with bulky disease. All were treated on unified guidelines; 63 (12.0%) had primary refractory disease, and 45 (8.6%) patients had a history of previous VTE. Results Venous thromboembolic events were reported in 71 (13.5%) patients. Among 121 patients with high (>3) ThroLy score, 22.3% developed VTE, compared to 8.4% and 12.4% in those with low- and intermediate-risk scores, respectively (P=0.014). Simplifying the ThroLy model into two risk groups; high-risk (score ≥3) and low-risk (score Conclusions ThroLy RAM can identify patients with DLBL at high risk for VTE. This model can be modified by dividing patients into two, rather than three, risk groups and further simplified by omitting neutropenia.