Primary cardiac lymphoma is very rare. This disease occurs mainly in immunocompromised patients and rarely in the immunocompetent. With the advent of echocardiogram, computed tomography and magnetic resonance imaging, more cases are being diagnosed ante-mortem although the prognosis still remains poor. These cardiac tumors provide unique diagnostic and therapeutic challenges. We present an interesting case of primary cardiac lymphoma diagnosed antemortem in an 81 year old immunocompetent female presenting as a large mass in the right atrium, right ventricle and encasing the right coronary artery; and asymmetric left ventricular hypertrophy, a variant of hypertrophic cardiomyopathy. Patient responded very well to chemotherapy with subsequent regression of the cardiac mass and ventricular hypertrophy.