Gastroduodenal pathology, functional disorders and inflammatory diseases of the biliary tract take leading position among the diseases of the digestive system in children. Precisely these clinical forms are more intensive then other nosology. Continuous screening questionnaire of 786 children aged 1.5 to 7 years was carried out to study the prevalence and risk factors for diseases of the digestive system in children. Based on retrieved data was determined that 47,1 +/- 3,5% of children had symptoms of gastro-intestinal tract and biliary system diseases. They met 2.3 times more often in children aged 4 to 7 years, than in children from 1.5 to 3 years old. Immerced examination revealed that the incidence of dyskinesia of the biliary tract was 33 +/- 3,3%, chronic gastritis (CG) and gastroduodenitis (GDD)--6,2 +/- 1,8%, chronic cholecystitis--4,2 +/- 1,4%, functional disorders of the stomach (FGD)--2,8 +/- 1,2% and duodenal ulcer (DU)--0,3 +/- 0,4% of cases. In the structure of digestive diseases in children from 1.5 to 7 years in the first place were DBT--70%, the second--CGD and CG--14.7%--the third chronic cholecystitis--8.9%, the fourth--FGD--5.9% and in fifth place--DU-0.5% of cases. At the care record in the pediatric clinic with diseases of the digestive system were registered only 7,9 +/- 1,9% of children, which is 5.9 times lower accordinig to data of active diagnostic. The leading medical and social risk factors and their complex influence on the formation of digestive diseases in infants and preschool children.