The aim of our studies was to evaluate the ultrastructural changes in the liver in rats after partial gastrectomy. The studied group consisted of 19 Wistar strain rats. In 15 animals partial gastrectomy was done. The control group underwent laparotomy, only. All tissue material was fixed and then prepared in a routinous way for histological and electron microscopy studies. During histological examinations no abnormalities were found. On the ultrastructural level (in tissue samples taken from animals, no more then 4 months after gastrectomy) we found mitochondrial degeneration, vacuolization of cytoplasm, abnormalities in the nuclei and increased activity of B-K cells. The focal necrosis of the hepatocytes was also observed. In tissue samples from animals after 4 to 12 months after primary operation we found increasing number and size of lipid vacuoles in the cytoplasm of hepatocytes The number of Ito cells increased, also. The gastrectomy caused only minimal ultrastructural changes in the liver tissue within the period of observation. Those changes described above may result from numerous metabolic derangements found after gastrectomy.