Infantile hypertrophic pyloric stenosis (IHPS) is a common surgical cause of vomiting in pediatric population. It usually occurs as an isolated condition or together with other congenital anomalies. There has been shown an association with genetic and environmental factors, younger maternal age, maternal smoking, bottle feeding, and erythromycin administration in the first two weeks of life. The patients typically present with projectile vomiting associated with symptoms of dehydration and acid-base abnormalities. On physical examination, an olive-like mass palpable in the right upper abdominal quadrant has decreased significantly over time, because of earlier diagnosis by imaging in ultrasound. Infantile hypertrophic pyloric stenosis is usually corrected through laparoscopic or open pyloromyotomy. However, preoperative preparation is essential to optimal outcome. Fortunately, the overall mortality after pyloromyotomy is less than 0.4% in most major centers and long-term sequels are rare.