Hirschsprung’s disease is a congenital disease characterized by absence of ganglion cells in hypertrophic nerve trunks in the distal bowel.Aim of work: To study the size and number of the submucosal nerve trunks in aganglionic segments of Hirschsprung’s disease and to evaluate the possibility of using this finding in diagnosis of Hirschsprung’s disease.Materials and methods: Fifty specimens from aganglionic segments from Hirschsprung’s disease and five specimens from age-matched control subjected without colonic innervation disorders were studied with H&E staining and micrometric studies.Results: Average density of submucosal nerve trunks in aganglionic segments and the control were 11.96 and 4.2 fiber per 10 HIPF, respectively. The maximum fiber size in the aganglionic segments was 120 micrometers compared to 35 micrometers in the control groups.Conclusion: There was a significant increase in number and size of the submucosal nerve trunks in aganglionic segments of Hirschsprung’s disease compared to control group and this finding can be used in the diagnosis of Hirschsprung’s disease.