Objective: This study aimed to investigate the effect of starvation and re-feeding on oxidative stress markers, lipid profile, thyroid hormones, and changes in thyroid tissue and in male Wistar rats.Method: Fifty-six male Wistar rats were divided into 6 groups. After 3 months of feeding animals with specific diet, the first group was used without fasting (day zero). Other rats were exposed to fasting for 14 days. The second group was considered as a group after fasting (day 14). In groups 3 to 6, replenishment was done and then these groups were euthanized on days 16 to 22, and blood and tissue samples were taken.Results: Significant increase was observed in MDA, triglycerides, and VLDL cholesterol. The concentrations of SOD, GPx and T3 were decreased significantly. By re-feeding, SOD, GPx, triglycerides, total cholesterol, and VLDL cholesterol increased. T3 concentration was significantly increased in all groups after re-feeding. In thyroid tissue, the diameter of follicles and the amount of colloid decreased and the number of parafollicular cells increased during starvation. By days 2 and 4 post-refeeding there were follicles with different sizes and the numbers of parafollicular cells were increased.