Abstract： Objective To investigate the prevalence of dentin hypersensitivity in Chinese urban adults aged between 20-69 years old and the factors related to dentin hypersensitivity.Methods The Chinese national survey on dentin hypersensitivity was conducted in 20-69 years old adults in six representative cities,Beijing,Shahghai,Guangzhou,Wuhan,Chengdu,and Xi'an in 2008.A muhi-stage stratified randomizing sampling method was used.Subjects were recruited from 36 urban survey sites in 6 cities. A structured questionnaire and a clinical examination on dentin hypersensitivity were used in the survey.The dentin hypersensitivity was diagnosed by a subject self-perceived short,sharp pain in resportse to a blast of cold air from a triple syringe administered to a tooth surface in 1 cm. Results In total,7939 twenty to sixty-nine years old subjects completed a structured interview and underwent a clinical examination on dentin hypersensitivity.Among them,40.7%(3230/7939) of the subjects reported being suffered from teeth sensitivity. When confirmed using a blast of air from a triple syringe and by ruling out other causes of sensitivity,such as caries,the prevalence was 29.7% (2354/7939),and the mean number of sensitive teeth was 1.4.The highest prevalence of dentin hypersensitivity[39.1%(622/1592)]was found in 50-59 years old group.The commonest teeth affected were the premolar teeth and the commonest initiating factor was cold drinks.Female,low education level,with gingival recession,attachment loss,and with the history of acidic substances derived from the stomach was related to dentin hypersensitivity.Conclusions Dentin hypersensitivity was comnlon in 20-69 years old Chinese urban adults.Dental professionals should give further emphasis to it.