The research included(53) cases collected from different regions of Mosul city, the cases were divided into two groups, the first group included (28) patients with down syndrome either the second group included (25) control group the study included assessment of hormone hepcidin, lnterleukin6, hormone TSH, irons, vitamin D3, , alkaline phosphatase, calcium, cholesterol total, very low density lipoprotein (VLDL), high density lipoprotein (HDL), , triglyceride, , hemoglobin, in serum of patients with down syndrome in compered with control group. get results increase in the levels of hormone Hepcidin, lnterleukin_6 ,hormone'sTSH , in patient down syndrome compared group control and decrease in the levels of ,Hb, iron in serum of patient group compared to control group. The results also indicate appositive correlation between hepcidin hormone and TSH ,Interleukin 6, , cholesterol, triglyceride, HDL-C,VLDL-C, LDL-C , and a negative correlation between hepcidin and vitamin D3, hemoglobin, lron ,Calcium, AlKalinephosphatase . Results indicate appositive correlation between Interleukin 6 with hepcidin hormone, calcium, triglyceride, VLDL-C ,and a negative correlation between Interleukin 6 with TSH ,vitamin D3, hemoglobin, lron , Alkaline phosphatase, total cholesterol, HDL-C,LDL-C.