Characteristics and regularities of structural reorganization of the liver in experimental cyclophosphamide hepatopathy were studied. Single injection of the drug caused pronounced morphofunctional changes in the liver (small focal hepatocyte necroses mainly in the periportal zone, mononuclear cell infiltration developing in the presence of circulatory disorders). The key event in the spatial reorganization of the liver after cyclophosphamide injection is reduction of hepatocyte volume density, increase of their surface density and surface/volume ratio. The percentage of binuclear hepatocytes increases in the liver early after cyclophosphamide injection; later the percentage of mononuclear cells increases. Other important changes in the spatial reorganization of the liver under the effect of cyclophosphamide are the increase in the volume and surface densities of sinusoids. These changes develop as a result of augmenting vascular plethora and blood cell stasis with the development of thrombosis during later periods.