Diffuse large B-cell lymphomas (DLBCL) make up bulk of the primary cardiac lymphomas. Lymphomas account for only 1% to 2% of primary cardiac tumors. They have been reported in immunocompromised (HIV+; transplant recipients) as well as immunocompetent individuals. The tumor is centered around the myocardium and involves right side of the heart more commonly than the left. Transesophageal echocardiography is the imaging modality of choice. The diagnosis can be made on a biopsy (open biopsy, endomyocardial biopsy, or percutaneous biopsy with imaging). The image shows a diffuse large B-cell lymphoma composed predominantly of centroblasts. The immunophenotypic and genetic features are similar to DLBCLs occurring in other sites.