Fibroblast growth factor -21 (FGF-21) is an adipocytokine with potent antidiabetic properties, that had been involved in the regulation of lipid and glucose metabolism. Aim: to assess the relationship between plasma levels of FGF-21 & Insulin resistance in cases with impaired fasting glucose, glucose intolerance and type 2 diabetes mellitus. Our case control study was conducted on eighty subjects, twenty with type 2 diabetes mellitus; twenty with impaired fasting glucose; twenty with impaired glucose tolerance; and twenty healthy subjects as our control group. All participants were subjected to full medical history thorough clinical examination and lab measuring of thorough clinical examination and lab measuring of serum FGF 21, FBG, 1hPPG, 2hPPG, HbA1c, FSI, HOMA-IR and lipid profile. Serum FGF-21 was higher in Type 2 diabetic patients, in impaired fasting glucose patients and in impaired glucose tolerance patients than in healthy group and highly significantly positively correlated with BMI, lipid profile (except HDL), indices of hyperglycemia, FSI and HOMA-IR. An inverse correlation was observed between Serum FGF-21 and HDL. FGF- 21 might play a role in the development of diabetes and in dyslipidemia associated with insulin resistance
