Objective To explore the relationship between the change in waist circumference (WC) and new onset diabetes (NOD) in a population of north China.Methods A total of 101510 subjects took part in the health examination from 2006 to 2007 for the employees of Kailuan Group.89364 subjects with fasting plasma glucose (FPG) ＜7.0 mmol/L,no history of diabetes,with complete data of FPG and WC,and without taking hypoglycemic agents were sclected as the observation cohort.Subjects who did not participate in the health examination from 2010 to 2011 and had incomplete data were finally excluded and thus 58426 subjects were included for final analysis.According to the baseline WC measurement and its quartile in the health examination during 2006 to 2007,the observed population was divided into two groups (obese group and non-obese 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 NOD.Results ( 1 ) The incidence of NOD in obese group was higher than that in non-obese group (8.02％ vs 3.37％,P＜0.01 ).Along with increasing WC in the 4 quartile groups,the incidence of NOD was progressively increased,being 2.32％,3.62％,5.46％,and 8.89％ respectively in the total population ( 2.84％,3.65％,5.32％,and 8.95％ in male,and 1.50％,3.41％,6.22％,and 8.51％ in female).( 2 ) Multiple logistic regression analysis showed that compared with the first quartile group,the second,third,and forth quartile groups had increased risks of NOD after adjusting age,gender,and other risk factors,the OR value being 1.17,1.47,and 1.95,respectively.After adjusting above factors in different genders,the influence of the second group on NOD in males and females was not significant,however,they still increased the risks of NOD,with the OR value being 1.08,1.36,and 1.90 in male,and 1.35,1.70,and 1.88 in female,respectively.Conclusion The incidence of NOD is increased with increasing WC.