Abstract: Objective To study blood pressure distribution and related factors among the children and adolescents in Hangzhou city.Methods A cross-sectional study was conducted among 52 prmiary and middle schools to collect physical examination information of 56 803 students aged from 6 to 19 years.Results Both the systolic blood pressure(SBP)and diastolic blood pressure(DBP)in the low-age groups of children and adolescents in Hangzhou ctiy were significantly higher than that of the national levels(P < 0.01).The SBP elevation rates of different gender-age groups were higher than that of the national levels of the same gender-age group as well(P < 0.01).Both the SBP and DBP levels were significantly higher in either over weight or obesity groups compared to that of the normal groups(P < 0.01).The results of binary logistic regression showed that body mass index was an important risk factor for both SBP(oddsrationOR=1.21,95% confidence intervalCI:1.20-1.22)and DBP(OR=1.15,95%CI:1.14-1.16).Conclusion The hypertension prevalence in childen is higher than that of in adolescents in Hangzhou city and closely associated with over weight and obesity.