Our purpose was to study the peculiarities of changing the hemostasis in children with chronic constipation. In the course of our investigation of hemostasis in children with chronic constipation, we found chronometric hypocoagulation with impairment of internal (XII, XI, IX, VIII) and external (II, V, VII, X) mechanisms of blood clotting, at the base of which is a deficit of vitamin K-dependent factors (II, VII, IX, X) and a slight impairment of the final stage of coagulation. In thrombocytovascular hemostasis, thrombocytopathy demonstrated increased adenosine-5-diphosphate aggregation and suppression of the internal route of fibrinolysis and endotheliosis. We must point out that all these changes lead to impairment of microcirculation in the form of thromboses, particularly in the submucous and mucous membrane vessels, which is confirmed by the morphologic findings. In the compensated form, chronometric hypocoagulation with a deficit of II, IX, and X factors is noted. In the subcompensated form, hypocoagulation increases, and the deficit of V and VII factors is in part the cause. Endotheliosis and the increase of the thrombogenesis dynamics are noted in the thrombocytovascular section. In the decompensated form, there is marked hypocoagulation. Low activity of antithrombin III leads to high content of fibrinmonomeasured complexes in combination with reduction of the thrombocytes quantity and to hypercoagulation. The present changes are confirmed by the morphologic research methods of studying the vascular channel of the large intestine wall, where organized thrombi and a marked plethora of neutrophil tissue infiltration are often revealed.