Cells in the tumor microenvironment (TME) of diffuse large B-cell lymphoma (DLBCL) show enormous diversity and plasticity, with functions that can range from tumor inhibitory to tumor supportive. The patient's age, immune status, and DLBCL treatments are factors that contribute to the shaping of this TME, but evidence suggests that genetic factors, arising principally in lymphoma cells themselves, are among the most important. Here, we review the current understanding of the role of these genetic drivers of DLBCL in establishing and modulating the lymphoma microenvironment. A better comprehension of the relationship between lymphoma genetic factors and TME biology should lead to better therapeutic interventions, especially immunotherapies.