Objective To study the interactive effect of job stress and genetic susceptibility (or gene polymorphism) on hypertension. Methods A cross-sectional epidemioiogical study was conducted in 452 workers from a thermal power plant in China. Extrinsic effort, occupational reward, and over-commitment were measured. Hypertensive patients were defined by three phases of screening, reexamination, and final diagnosis. β2-AR genotypes and allele frequencies at amino acid positions 16 (β2-AR-16:Arg→Gly) and 27(β2-AR-27:Gln→Glu) were identified by PCR-RFLP. Results Job stress was related with the prevalence of hypertension in males (P0.05). Differences in genotypes and allele frequencies of the β2-AR-16 were statistically significant between the hypertension and control groups (P0.05). The prevalence of hypertension was higher in individuals carrying Gly16 allele than in those carrying Arg16 allele of the high job stress group (P