Background: Hirschsprung's disease (HD) is a developmental disorder of the enteric nervous system that is characterized by the absence of ganglion cells in the myenteric and submucosal plexus from the anorectum for a variable colonic or intestinal distance. HD is a congenital bowel motility disorder which occurs in approximately one of every 5000 live births. This results in a lack of peristalsis leading to a huge dilatation of the colon proximal to the aganglionic bowel. Aim of work: The purpose of the present study is to investigate the clinical impact of delayed management of children with HD. and how it would affect their outcomes? Methods: The present study was performed in the period from July 2018 to august 2019 in Pediatric Surgery Department of Zagazig University Hospital. 18 patients enrolled inprospective clinical study Results: The delayed diagnosis of HD is associated with a different pattern of presentation compared with neonatal HD. Most of the cases were presented by chronic constipation, abdominal distension and bilious vomiting. Moreover, outcome is worse in older children who are diagnosed with this disease. Conclusions: HD in older children associated with long hospital stay, increased cost of treatment compared with the younger children. Postoperative outcome in older children associated not only with increased risk of serious morbidities but also indirectly affect their long-term outcome.