Meckel's diverticulum is generally acknowledged to be the most prevalent congenital anomaly of the gastrointestinal tract. The preoperative diagnosis of Meckel's diverticulum is difficult, especially in neonates, because of the lesions ability to masquerade as one of a variety of much more common abdominal pathologies. Recently we experienced a case of perforated Meckel's diverticulum with mild inflammatory reaction, intestinal adhesion, and small bowel obstruction in a previous healthy 9-day-old neonate. The spontaneous perforation of Meckel's diverticulum in neonate is very rare but serious entity. The course was rapid and progressed to sepsis. So despite its varied presentation, Meckel's diverticulum should be kept in mind as a cause of acute abdomen in neonates.