Rhabdomyosarcoma is a rare malignant tumor of the heart that accounts for 20% of all primary malignant neoplasms of the heart. Symptoms vary in accordance with the location of the mass; unfortunately, by the time the patient becomes symptomatic, the tumor has already metastasized to other organs. Diagnosis is frequently obtained via transthoracic or transesophageal echocardiography and nuclear magnetic resonance imaging. Surgery is indicated for malignant cardiac neoplasms to relieve cardiac symptoms and to prolong patient survival. Subsequent postoperative chemotherapy or radiotherapy is necessary, and the long-term prognosis is poor. We present a case of a primary cardiac rhabdomyosarcoma that arose from the lateral wall of the right atrium and required implantation of a permanent cardiac pacemaker after surgery.