Although statins reduced cardiovascular mortality, these drugs did not prevent myocardial infarction in some patients. Previous studies showed that genetic variation in cholesteryl ester transfer protein (CETP) gene was linked to this response. The identified gene is characterized by two different variants: B1 and B2 alleles identified by the presence and absence, respectively, of a restriction site for the enzyme Taq1 in intron 1. The present study identified the variation in Taq1B of the gene using Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) in 130 patients. An association study of Taq1B with the response of 24 middle-aged dyslipidemic patients to simvastatin treatment for 8 weeks was also done. The overall allele frequencies of B1 and B2 alleles were 0.548 and 0.462, respectively. The genotype frequencies were in Hardy-Weinberg equilibrium. The distinguishing feature of individuals with B1B1 genotype when treated with simvastatin was their rapid increase in high density lipoprotein (HDL) observed after 2 weeks which continued till the 8th week treatment. The expected HDL elevation among individuals with B1B2 genotype was observed only after the 8th week simvastatin treatment.