Abstract: To investigate the effects of acute hypoxic stress on the gill organs and liver tissue damage of juvenile Eleutheronema tetradactylum, a 2 h acute hypoxic stress experiment was conducted with 2 mg/L of dissolved oxygen in the water. Then the gills and liver organs of E.tetradactylum were observed using conventional paraffin sections and HE staining as well as electron microscopic techniques. The results displayed contraction of the blood sinuses in the gill filaments of E.tetradactylum under acute hypoxic stress, with dilated ends; longer gill lamellae, larger intervals and swollen and bulging parts of the epithelium. The parietal crypt of mitochondria-rich cells changed from concave to flat and the intracellular mitochondrial morphology changes from oval to round. Liver tissue showed hepatocyte necrosis and fusion of hepatocytes. Hypoxic stress had a large effect on the gill and liver tissues of E.tetradactylum and caused structural damage to the tissues by 2 h.