AIM: To evaluate the specific computed tomography (CT) imaging criteria for differentiating tuberculosis involving the small bowel mesenteric lymph nodes from lymphomas.METHODS: We retrospectively reviewed the anatomic distribution,CT enhancement patterns of lymphoma in 18 patients with mesenteric tuberculosis and 22 with untreated non-Hodgkin's lymphomas (NHL) involving small bowel mesentery (SBM).Of the 18 patients with tuberculosis,9 had purely mesenteric tuberculous lymphadenopathy (TL),and 9 had mesenteric TL accompanied with tuberculous mesenteritis (TLM).RESULTS: CT showed that tuberculosis and NHL mainly affected lymph nodes in the body and root of SBM.Homogeneously enhanced lymph nodes in the body and root of SBM were found more often in the NHL (P＜0.05).Homogeneously mixed peripheral enhanced lymph nodes in the body of SBM were found more often in mesenteric TL and TLM (P＜0.05).Peripheral enhanced lymph nodes in the root of SBM were found more often in mesenteric TL and TLM (P＜0.01)."Sandwich sign" in the root of SBM was observed more often in NHL (P＜0.05).COMCLUSION: Anatomic lymph node distribution,sandwich sign and specific enhancement patterns of lymphadenopathy in SBM on CT images can be used in differentiating between tuberculosis and untreated NHL involving SBM.