PURPOSE: To compare the characteristics of tubercular vs. leukemic involvement of abdominopelvic lymph nodes using multidetector computed tomography (CT). MATERIALS AND METHODS: We retrospectively reviewed multidetector computed tomography features including lymph node size, shape, enhancement patterns, and anatomical distribution, in 106 consecutive patients with newly diagnosed, untreated tuberculosis (55 patients; 52%) or leukemia (51 patients; 48%). In patients with leukemia, 32 (62.7%) had chronic lymphocytic leukemia, and 19 (37.3%) had acute leukemias; of these, 10 (19.6%) had acute myeloid leukemia, and 9 (17.6%) had acute lymphocytic leukemia. RESULTS: The lower para-aortic (30.9% for tuberculosis, 63.2% for acute leukemias and 87.5% for chronic lymphocytic leukemia) and inguinal (9.1% for tuberculosis, 57.9% for acute leukemias and 53.1% for chronic lymphocytic leukemia) lymph nodes were involved more frequently in the three types of leukemia than in tuberculosis (both with p <0.017). Tuberculosis showed peripheral enhancement, frequently with a multilocular appearance, in 43 (78.2%) patients, whereas patients with leukemia (78.9% for acute myeloid leukemia and acute lymphocytic leukemia, 87.5% for chronic lymphocytic leukemia) demonstrated predominantly homogeneous enhancement (both with p <0.017). For the diagnosis of tuberculosis, the analysis showed that a peripheral enhancement pattern had a sensitivity of 78.2%, a specificity of 100%, and an accuracy of 88.7%. For the diagnosis of leukemia, the analysis showed that a homogeneous enhancement pattern was associated with a sensitivity of 84.3%, a specificity of 94.5%, and an accuracy of 89.6%. CONCLUSION: Our findings indicate that the anatomical distribution and enhancement patterns of lymphadenopathy seen on multidetector computed tomography are useful for differentiating between untreated tuberculosis and leukemia of the abdominopelvic lymph nodes.