Abstract: The present study investigated the deleterious effects of MDA on the growth, morphology, structure and related enzyme activity of intestinal epithelial cells (in vitro) isolated from Ctenopharyngodon idella. MDA reduced cell activity. Cell survival at the range of 1.23-9.89 g/L for 3-9h treatments; the highest inhibition was at 6 hour. MDA also reduced cell adhesion and colony formation. With the concentration of 4.94 g/L MDA induced the formation of fat droplets and vesicles, swelling mitochondria, and karyopycnosis. MDA inhibited cell differentiation, induced intracellular enzyme leakage, and increased organelles membrane permeability. MDA significantly reduced the activity of GSH-PX and T-AOC in culture medium (P0.05). In conclusion, MDA at the concentration range of 1.23-9.89 g/L damaged the dissociated IECs from Ctenopharyngodon idella by disregulating cell growth, cell morphology, cell structure, and lipid peroxidation. The extent of damage is correlated with the concentration and incubation time.