The effects of external melatonin on Muzaffarnagri sheep's Endocrine function, Physiological parameters, and Oxidative stress are examined in this study. The study, which took place at Acharya Narendra Deva University of Agriculture and Technology Uttar Pradesh, in College of veterinary science Ayodhya. Divided the participants into 4 groups: one that received melatonin and another that did not receved the drug. Important metrics tracked were levels of the stress hormone cortisol, activity of the antioxidant enzyme superoxide dismutase (SOD), and vital signs such core Body temperature, Pulse rate, and Respiration rate and Heart rate. Was measured during trail period The results showed that the group treated with melatonin had significantly lower cortisol levels, indicating less stress. An increase in superoxide dismutase (SOD) activity was indicative of better antioxidant defense in the treated group. Melatonin had a beneficial effect on the sheep's health as a whole, as indicated by the increased stability of their physiological markers. Supplementing ewes with melatonin may improve their health and productivity by reducing stress and oxidative damage, according to this study.