Inflammatory pseudotumor of the lung was first described by Brunn in 1939. Since that description, various extrapulmonary sites of inflammatory pseudotumor have been described. Review of the literature reveals five cases of inflammatory pseudotumor involving the heart, but no cases have been reported in the radiology literature. The present case involves a 7-month-old girl with inflammatory pseudotumor involving the right atrium, which was completely excised at surgery. Though rare, inflammatory pseudotumor should be considered in the differential diagnosis of cardiac tumors in children.