Introduction & Objective: Hirschsprung's disease (HD) is a motor disease caused by defects in the migration of nerve cells during the development of the gastrointestinal tract, which causes functional obstruction. The present study investigates the hypothesis that the absence of nerve trunk hypertrophy in a biopsy specimen is associated with a longer segment of aganglionosis. Materials & Methods: Demographic characteristics of patients such as age, sex, type of surgery, length of the involved part during surgery were recorded and then patients' pathological specimens were recorded in terms of diameter and number of nerve trunks and then the relationship between nerve trunk diameter in ganglion-free segment and intestine without the ganglion was examined. Chi-square test and Fisher's exact test were used for analytical data. Results: Twenty five children with Hirschsprung's disease were examined according to gender and age, boys were the most frequent and the majority of patients were infants. As expected, the most affected site was the rectosigmoid. Out of 25 patients, 6 patients had a nerve trunk less than 40 micrometers, of which only 2 patients had involvement of the entire colon. No correlation was found between nerve trunk diameter and age, sex, and length of the involved intestine. Conclusions: The hypothesis that the lack of hypertrophy of the nerve trunk could be associated with more severe intestinal involvement and a more proximal transition zone was not confirmed. The results can be said that in HD, hypertrophy of the nerve trunk is seen in the pathology specimen in the aganglionic segment.