It has been reported that the beta3-adrenergic receptor gene (ADRB3) is associated with abnormal metabolic risk factors. Therefore, we examined whether the Trp64Arg polymorphism of ADRB3 affects the occurrence of metabolic syndrome (MS). The participants were 2,395 subjects who underwent a medical examination in Shigaraki in Shiga, Japan. Among them, 1,416 subjects who gave informed consent for genetic analysis and were not receiving treatment for hypertension, diabetes, or hyperlipidemia were enrolled in this study. MS was diagnosed in 86 (16.0%) of 537 men, and 8 (0.9%) of 879 women. There was no significant relationship between ADRB3 polymorphism and the frequency of MS. Multiple logistic regression analysis including smoking, sex, and age as confounding factors showed no interaction between MS and ADRB3 polymorphism (odds ratio: 0.94; 95% confidence interval: 0.59-1.49; p=0.78). Subjects were also analyzed according to differences in the number of abnormal metabolic risk factors. However, there was no significant relationship between ADRB3 polymorphism and the number of such factors. In conclusion, in a general sample, the frequency of MS was 16.0% in men, and 0.9% in women. There was no relationship between ADRB3 polymorphism and MS.