Symptoms of bicuspid aortic valve usually occur in the age group of 50-70 years, but rarely, it can also lead to sudden unexpected death in infancy and early childhood. The autopsy of a 2-month-old baby boy, found dead in his cot, revealed the heart weight as 25 g, and the macroscopic examination showed the circumference of the aortic valve consisting of two leaflets as 8 mm. The thickness of the left ventricle, right ventricle, and septum was measured as 8, 7, and 10 mm, respectively. Microscopically, the heart revealed hypertrophic changes of myocytes. Subendocardial areas displayed necrosis of myocytes, and severe and diffuse ischemic changes characterized by loss of myofibers and vacuolization. Interstitial pneumonia was identified in the lungs. Death occurred as a result of a congenital bicuspid aortic valve obstructing the left ventricular outflow tract complicated by lung infection. As there are only a few reported cases in infancy, and congenital bicuspid aortic valve can lead to sudden unexpected death, this case is presented to the forensic community. Copyright © 2006 by American Academy of Forensic Sciences.