Aneurysms arising from the sinus of Valsalva are a rare cardiac defect that can present with various signs and symptoms, and if not diagnosed and treated rapidly can lead to fatal outcomes. Unruptured aneurysms are usually asymptomatic and found incidentally during diagnostic studies. More commonly, aneurysm of sinus of Valsalva is detected after the occurrence of rupture. Echocardiography has become the investigative tool of choice for this condition, not only for diagnosis but also for quantification of severity. We hereby report a rare case of a 15-year-old patient presenting with complaints of effort dyspnea and palpitations. Two-dimensional transthoracic echocardiography (TTE) showed aneurysmal dilatation of left sinus of Valsalva which had ruptured into the left ventricle. Also, there was an intimal flap within the sinus of Valsalva aneurysm. The anatomical relationship between the aorta, aneurysm, and the left ventricle as well as the intimal flap within the aneurysm was clearly delineated with the help of three-dimensional TTE. After confirmation of the diagnosis with multidetector computed tomography, patient underwent successful surgical repair of the defect.