Objective: To explore potential risk factors of isolated diastolic hypertension(IDH)among young and middle-aged Chinese.Methods: A community-based cross-sectional study was conducted among 338 subjects,aged 25 years and above,using random sampling technique.There were 68 cases of IDH,46 cases of isolated systolic hypertension(ISH),89 cases of systolic and diastolic hypertension(SDH),and 135 of subjects with normal blood pressure.Cases and controls were matched on sex by frequency matching.Demographic characteristics,blood pressure and other relevant information were collected.Results: Compared with controls,patients with IDH and ISH had significant higher level of triglyceride,high density lipoprotein,blood glucose and body mass index(BMI)(p < 0.05); while patients with SDH had significantly higher level of total cholesterol,triglyceride,glucose and BMI(p < 0.05).Linear mixed effects model showed that drinking tea,family history of hypertension(FHH),higher blood glucose,triglyceride and low density lipoprotein were related with elevated diastolic blood pressure(DBP)(p < 0.01); HFH,blood glucose,creatinine and BMI have positive effect on systolic blood pressure(SBP)(p < 0.05).Conclusions: Drinking tea,FHH,high levels of triglyceride,high density lipoprotein,blood glucose and BMI are associated with IDH among young and middle-aged Chinese.