Morphological examination of isolated enterocytes obtained-from the rat jejunum initial region by mechanical method after the previous treatment with ethylendiamintetracetic acid disodium salt included staining with hematoxylin, carmin and janus green. Histochemical reaction to alcaline phosphatase, succinate dehydrogenase, lactate dehydrogenase, ATP-ase and glycosaminoglycans were performed. Significant resemblance between the main cytological and cytochemical characteristics of the isolated enterocytes and those of the intestinal epithelium was demonstrated. Morphophysiological examination of isolated enterocytes, incubated in media, containing different substrates (glucose, maltose, glycine, trioleine) and under effect of oxygenated and not-oxygenated media demonstrated that mitochondria intracellular topography and succinate dehydrogenase activity significantly depend on their functional state.