Abstract： To investigate the prevalence and risk factors of stress urinary incontinence in women of Miyun County.Questionnaire survey was conducted in 8665 residents selected from urban and rural areas of Miyun County.Total 8663 questionnaires were completed with a response rate of 99.98％.The prevalence of urinary incontinence was 34.43％ (2983/8663),among which 1790 cases were of stress type with a prevalence rate of 20.66％,414 cases were of urgent type with a prevalence rate of 4.78％ and 779 cases were of mixed type with a prevalence rate of 8.99％.The risk factors of the stress urinary incontinence were advanced age(OR =1.555),BMI≥24 kg/m2 (OR =0.556),alcohol drinking(OR =1.308),constipation (OR =1.360),delivery times≥3(OR =1.998),history of macrosomia-bearing (OR =0.572).