Cardiac myxoma is rare in children. Myxomas are exceedingly rare in infancy. Right atrial myxomas were recorded in a small number of case reports involving infants worldwide. We report the case of a 2-month-old infant with giant right atrial myxoma. The case presented to our hospital with respiratory distress, and had pericardial and pleural effusion. Diagnosis of cardiac tumor was made with the aid of computerized tomography scan and echocardiogram. The tumor size was 3.1 x 3.4 x 3.9 cm. The patient worsened rapidly and had sudden cardiac arrest which did not respond to interventions. Postmortem cardiac autopsy confirmed the diagnosis of myxoma on gross examination and histology. This article aims to focus attention to the atypical size and location of this atrial myxoma, causing diagnostic difficulty in this infant.