Primary cardiac lymphoma (PCL) is a rare presentation of lymphoma in children. The emergency nature of its presentation (heart failure and arrhythmias) makes management of this entity difficult. The authors describe two children with lymphoma primarily involving the heart; one patient was a case of PCL and the other was a case of lymphoma involving the heart along with pelvic involvement. These two patients, together with a literature review on the topic, suggest that if the diagnosis of PCL is made early and treatment is expeditiously started, patients may do well.