Plain language summary Hypertension in Chinese adolescent is generally ignored. This study first reports the prevalence of hypertension in adolescents in Yunnan Province, China. Four thousand seven hundred and eighty-one freshmen were surveyed and height, weight and blood pressure were measured. A decision tree model was used to analyze the predictors of hypertension. The study demonstrated that gender, BMI, only children and red wine predict hypertension in adolescents. Purpose Previous studies have indicated that the prevalence rate of hypertension in adolescents is high, but it has not received much attention and the influencing factors are unclear, especially in Yunnan Province, China. Materials and methods A cluster sampling method was used to investigate 4781 freshmen in a college in Kunming, Yunnan Province from November to December. Demographic and lifestyle data were collected using questionnaires, and height, weight and blood pressure were measured. Decision tree model of hypertension in college students was established by Chi-square automatic interactive detection method. Results Prevalence of prehypertension of systolic blood pressure (SBP) and diastolic blood pressure (DBP) were detected in 33.9% and 32.1%, respectively. Prevalence of hypertension of SBP and DBP was detected in 1.2% and 7.2%, respectively. The hypertension and prehypertension decision tree of SBP has gender (& chi; (2) = 728.64, p < .001) at the first level and body mass index (BMI) (boys: & chi; (2) = 55.98, p < .001; girls: & chi; (2) = 79.58, p < .001) at the second level. The hypertension and prehypertension decision tree of DBP has gender (& chi; (2) = 381.83, p < .001) at the first level, BMI (boys: & chi; (2) = 40.54, p < .001; girls: & chi; (2) = 48.79, p < .001) at the second level, only children (& chi; (2) = 6.43, p = .04) and red wine consumption (& chi; (2) = 8.17, p = .017) at the third level. Conclusions The present study suggests that gender, BMI, only children and red wine consumption were the main factors affecting hypertension in college students in southwest border areas of China.