The present research was conducted to investigate the impacts of oxytocin injection on lactating buffaloes. One group of buffaloes was injected with 30 IU of oxytocin at each milking, while second group was kept as control without any treatment. A significant higher level (P?0.01) of glucose, total cholesterol, LDL-C, triglycerides, total proteins and CRP was found in oxytocin injected lactating buffaloes. The serum total oxidant status and total antioxidant status were found to be significantly higher and lower respectively in the oxytocin injected lactating buffaloes. The overall mean serum PON1 and arylesterase concentration was significantly lower while malondialdehyde, total homocysteine and ceruloplasmin was increased significantly in the oxytocin injected lactating buffaloes. The liver enzymes like serum AST and ALT concentration did increase significantly in the oxytocin treated group. Serum T3, estradiol and progesterone was significantly (P?0.05) high in the oxytocin injected lactating buffaloes. Long use of oxytocin did effect the serum composition and animal health.