Primary cardiac tumors are quite rare, especially in the pediatric age group, and their atypical presentations often prevent a timely diagnosis. Most primary cardiac tumors in the pediatric age group are benign. Fibromas are generally reported as the second most common primary cardiac tumors in the pediatric age group. These neoplasms are often intramural and involve the left ventricular free wall or the interventricular septum. Although benign, fibromas may become life-threatening by causing arrhythmias or obstruction to the blood flow. A case of supravalvular intraluminal ascending aorta fibroma in a 23-month-old girl, presenting with syncope, is described here; the location is rare and the presentation atypical for this type of tumor. Transesophageal echocardiography helped us to evaluate the anatomic details of the tumor and plan surgery.