ABSTRACT Introduction: Metabolic Syndrome is a potential threatening factor for cardiovascular disorders and atherosclerosis which is accompanied by increase in plasma Triglyceride,cholesterol, LDL-c, Fasting blood sugar (FBS) and low level of High density lipoproteins (HDL-c). Cholesteryl ester transfer protein (CETP) catalyzed transfer natural lipids and phospholipids between lipoproteins. CETP can have a significant role in balancing the quantity of plasma lipids and lipoproteins. The present survey attempts to show the association of I405Vpolymorphisms in CETP gene with metabolicsyndrome parametersan Iranian populations. Methods: In order to identify the association between the I405V polymorphisms of this gene and the lipid pattern of plasma and other parameters of metabolic syndrome, the quantity of Lipids in metabolic Syndrome(N=120) and Normal individuals(N=200) were measured. The abundance of alleles and genotypic distribution of the I405V polymorphisms were defined along with comparison between two control and patient groups.. Blood samples were collected then followed by routine biochemical analysis, DNA extraction performed. Polymerase chain reaction-restriction fragment length polymorphism was applied to identify I405Vpolymorphism. Statistical analyses were applied using SPSS software. Results: lipid pattern of plasma and other parameters of metabolic syndrome had significant different between the patient and control groups. Also the abundance of alleles and genotypic distribution of this polymorphism showed a significant difference between two groups. I405V polymorphism, chosen in the samples, was accompanied with metabolic syndrome. Conclusion: The results confirm that in metabolic syndrome patients. These genetic mutation in CEPT gene are accompanied with change in lipids profile and other metabolic syndrome parameters.Our study suggest that the promoting effect of I405V polymorphism in process of metabolic syndrome disorder. We obtained that this polymorphism can increase occurrence of metabolic syndrome. Our results showedI405V polymorphism are associated with some MS-associated variables in our population