We describe a case of ruptured aneurysm of the left coronary sinus of Valsalva diagnosed by transthoracic two-dimensional echocardiography. A very few cases with ruptured left sinus of Valsalva have been reported. We are reporting a rupture of the left sinus of Valsalva into the main pulmonary artery in a 40-year-old male diagnosed by transthoracic echocardiography.