Left atrial fibroma as a benign tumor is an exceedingly rare left atrial mass. It has various clinical signs and symptoms and sometimes leads to serious complications such as lethal arrhythmia and death. We report a case of right atrial fibroma in a 40-year-old male who presented with dyspnea and atrial fibrillation. Transthoracic echocardiography revealed a large sessile mass attached to interatrial septum near the coronary sinus valve in the right atrium. The patient underwent surgical resection of tumor through the right atrium. The postoperative course was unremarkable. Histopathological examination showed that it was a fibroma. The 6-month follow-up revealed that the patient was in well condition with no evidence of tumor recurrence.