Physical inactivity is known to cause many health problems globally each year. However, evidence regarding the interaction between excessive physical activity (PA) and blood pressure in young and middle-aged populations is limited.A multistage, stratified, random cluster sampling design was adopted to recruit representative samples. Participants were asked to complete a questionnaire and undergo physical examinations. Associations between prehypertension, hypertension and PA durations were examined by multivariable logistic regression.Overall, 8206 subjects (4110 men, 50.1%) aged 15 to 45 years were enrolled. The prevalence rates of prehypertension and hypertension were 45.7% and 5.0%, respectively. Among the 1913 participants who performed moderate-intensity PA for more than 700 min/wk, 118 had hypertension (6.2%) and 845 had prehypertension (44.2%). Among the 1003 participants who performed vigorous-intensity PA for more than 450 min/wk, 82 had hypertension (8.2%) and 479 had prehypertension (47.8%).Long-term and sustained PA may increase the risk for hypertension in young and middle-aged subjects. An appropriate recommendation of PA duration should be encouraged in this cohort.