Diffuse large B-cell lymphoma (DLBCL) is a highly common type of malignant and heterogeneous non-Hodgkin's lymphoma. Tumor-associated macrophages, specially the M2-type, promote tumor progression and drug resistance. The clinical outcome of patients with high neuron-specific enolase (NSE) expression is worse than that with low NSE expression. The tumor-promoting mechanism of NSE, however, remains unclear. This study explored the role of NSE in macrophage polarization associated with the immune microenvironment of DLBCL. Our results showed that NSE protein expression was higher in lymphoma cell lines than in the B lymphocytes. Functional studies demonstrated that upregulation of NSE in lymphoma cells could promote M2 polarization and migration ability of macrophage, thereby consequently promoting the progression of lymphoma in vitro and in vivo. Further mechanism studies revealed that lymphoma-derived exosomes could mediate NSE into macrophages, NSE enhanced nuclear p50 translocation with subsequent defective classical nuclear factor-κB activity in macrophages. These results indicate that NSE may be a potential target for lymphoma therapy and a prognosis marker for lymphoma.