Abstract： Objective To investigate the relationship between IRS-1 gene polymorphism and plasma glucose level. Methods 56 6 individuals in the present study were the first generation relatives and their spouses of 184 hypertensive families and 99 families with normal blood pressure . Fasting levels of plasma glucose, insulin, triglyceride and fibrinogen were de termined. The polymorphism of IRS-1 gene was determined by PCR/BslN1 digestion. Results (1) The frequency of Gly/Arg genotype of IRS-1 gene was not different in subjects with or without family history of hypertension. (2 ) After adjusting age, sex and BMI the frequencies of Gly/Arg genotypes were sig nificantly higher in the highest FPG-Tertile [FPG (5.35±0.01) mmol/L] than in the lowest FPG-Tertile [FPG (4.19±0.02) mmol/L], the OR was 3.28. Conclusions The genotype of Gly/Arg in IRS-1 gene is related with a higher plasma glucose level in these non-diabetic population, which suggests it may be one of the genetic factors contributing to the development of diabete s in population in Da-qing