Objective: To investigate the relationship of insulin resistance and the polymorphisms of insulin receptor-related genes in essential hypertension patients of two different kinds of TCM constitution. Methods: Oral glucose tolerance test (OGTT) and insulin release test (InRT) were conducted in 217 essential hypertensive patients of either sluggish meticulous (SM) constitution (139 cases) or prosperous impetuous (PI) constitution (78 cases), and the polymorphism of three genes,including insulin-like growth factor-1 receptor (IGF-1R), insulin receptor substrate-1 (IRS-1) and 2 (IRS-2) genes were detected. Results: (1) OGTT, InRT and insulin resistance index (Homa-IR) were higher and insulin sensitive index (ISI) was lower in the patients of SM constitution than those in patients of PI constitution. (2) Significant difference of ISI and Homa-IR was shown in patients of both constitutions with genotype G of the 3 genes. Conclusion: Decrease of insulin sensitivity and increase of insulin resistance are more obvious in hypertensive patients with genotype G of the 3 genes of SM constitution than in those of PI constitution. Therefore, the difference in constitution might be one of the genetic characteristics for insulin resistance in hypertensive patients.