BackgroundPrehypertension (PHT) and hypertension (HTN) in young adults are essential risk factors for other cardiovascular diseases (CVD) in later years of life. However, there is a lack of knowledge about the burden and risk factors of PHT/HTN for Vietnamese youth. The aim of this study was to investigate the prevalence of PHT/HTN and risk factors among university students in Hanoi, Vietnam.MethodsThis study was designed as a cross-sectional investigation with 840 students (394 males and 446 females) randomly sampled from freshmen of Vietnam National University, Hanoi (VNU). Socio-demographic, anthropometric, and lifestyle data were collected using questionnaire forms and physical measurements. HTN was defined as blood pressure (BP) ≥ 140/90 mmHg and/or current treatment with antihypertensive medications. PHT was defined as a systolic BP from 120 to 139 mmHg and/or a diastolic BP from 80 to 89 mmHg. Body mass index (BMI) was classified according to the WHO diagnostic criteria for Asian adults: normal weight (BMI 18.5–22.9 kg/m2), underweight (BMI < 18.5 kg/m2), overweight (BMI 23–24.9 kg/m2), and obese (BMI ≥ 25 kg/m2). Bivariable and multivariable log-binomial regression analyses were conducted to explore the association of PHT/HTN with different risk factors.ResultsThe overall prevalence of prehypertension and hypertension was 33.5% [95% CI: 30.3–36.8%] (54.1% in men and 15.3% in women) and 1.4% [95% CI: 0.7–2.5%] (2.5% in men and 0.5% in women), respectively. Regarding CVD major risk factors, 119 (14.2%) were identified as overweight/obese, 461 (54.9%) were physical inactivity, 29.4% of men and 8.1% of women reported consuming alcohol. The multivariable analysis indicated the male sex (adjusted prevalence ratio [aPR] = 3.07; 95% CI: 2.32–4.06), alcohol consumption (aPR = 1.28; 95% CI: 1.03–1.59) and obesity (aPR = 1.35; 95% CI: 1.08–1.68) as the independent risk factors for PHT/HTN.ConclusionsThe results revealed the high burden of prehypertension and hypertension among university freshmen in VNU. Male sex, alcohol consumption, and obesity were identified as important risk factors for PHT/HTN. Our study suggests an early screening program for PHT/HTN and campaigns to promote a healthy lifestyle for young adults in Vietnam.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12889-023-16118-4.