Congenital megacolon is one of the most common diseases in pediatric surgical practice. Although this is a common disease, the results of treatment varies between each surgeon and institute. Some patients have severe post-operative complications which cause disable and eventually death. Better understanding in the disease in every aspect will improve treatment outcomes and decrease post-operative complications. In the last decade, new knowledge about the disease has been found. The author reviews the disease in the aspect of pathophysiology, diagnosis, and treatment.