Aim To explore the effect of waist circumference （WC） on the detection rate of carotid plaque in the middle-aged and elderly people. Methods Prospective cohort study method was used in this study. A total of 5852 individuals were stratified randomly and selected from the 101510 participants in Tangshan Kailuan Company community in 2006～2007 health examination survey. A total of 5440 people （age above 40 years old,free of stroke,free of TIA or free of mycardial infarction） were enrolled in this study. A total of 3 individuals who had no waist circumference information were excluded and thus 5437 subjects were included for final analysis. It contained 3255 males and 2182 females,the average age was 55.2±11.8 years. According to the baseline WC measurement and its quartile in the health examination during 2006～2007,the observed subjects were divided into two groups （central obesity group and non-obesity group） or four groups （first,second,third and forth quartile groups）. Multiple Logistic regression analysis was used to test the relation between the change in WC and the detection rate of carotid plaques. Results The detection rate of carotid plaques in central obesity group was higher than that in non-obesity group （57.1% vs.42.9%,P<0.01）. Along with increasing WC in the 4 quartile groups,the detection rate of carotid plaques was progressively increased,being 43.6%,53.0%,58.0%,and 61.0%,respectively in the total population. Multiple Logistic regression analysis showed that compared with the first quartile group,the second,third and forth quartile groups had increased risk of carotid plaques,the OR value was 1.203,1.305 and 1.302,respectively. Conclusion The detection rate of carotid plaques was increased with increasing WC in the middle-aged and elderly population.