Introducton: Constipation is a worldwide problem. Current research aimed to study the various determinants of functional constipation and clinical spectrum in north Bihar. Thus creating tangible evidence for the policy makers. Material and methods: Retrospective hospital record based cross sectional study was conducted at tertiary care Darbhanga medical college and hospital (DMCH). Children between 2-12 years with chief presenting complaint of constipation in pediatric OPD and IPD during July 2013 to June 2014 were identified. Only those who fulfilled the ROME 3 criteria of functional constipation were included in the study. Children with any organic cause of functional constipation and children getting treatment for functional constipation were excluded from the study. Results: Total 892 children were examined during the study period, of which 343 children were diagnosed to have constipation. Among them 315 (35.31%) children were qualified to have functional constipation as per ROME 3 criteria. 28 cases (3.14%) have organic cause of which 15(53.57%) had Hirschprung's disease Mean age of toilet training was 17.2 months. Females were more affected (61.58%) than males. Maximum cases were between 2-5 yrs (62.2%), lower socioeconomic status (56.19%)and rural background (50.15%).lack of indoor toilets and dirty school toilets precipitates constipation particularly in girls. Conclusion: constipation causes physical, psychological morbidity and poor quality of life, hence early diagnosis and management is of utmost importance. Lack of indoor clean toilets, early toilet training, unhygienic school toilets, improper roughage intake should be taken care of by parents/ authority.