Objective: Introduction: Prehypertension is a risk factor for hypertension and other cardiovascular diseases. Determining its prevalence and associated risk factors in young populations may indicate appropriate preventive measures. We estimated prehypertension prevalence and risks among healthy medical and paramedical students. Methods: This cross-sectional study was conducted on 437 students at King Abdulaziz University in Jeddah, Saudi Arabia. Socio-demographic characteristics and medical history were obtained by validated self-administered questionnaires. Weight, height, waist circumference, and body mass index were determined. Blood pressure was recorded under standardized conditions. Prehypertension was defined as systolic blood pressure of 120–139 mmHg and/or diastolic blood pressure of 80–89 mmHg. Significant prehypertension predictors were identified by multivariate logistic regression analysis. Design and method: Subjects’ average age was 21.1 ± 1.4 years. Prehypertension was more prevalent among male students (36%) than female students (7%) and was predominantly diastolic in female students (90.5%). Prehypertensive subjects (17%) had significantly higher body mass index. Male students had a higher prehypertension risk (odds ratio 8.4; 95% confidence interval 4.1?17.0). Mean heart rate significantly predicted prehypertension (1.05; 1.02?1.08).Current smoking and obesity (body mass index ?30 kg/m2) increased prehypertension risk (3.6; 1.1?12.3 and 2.3; 1.1?5.0, respectively), but not age, monthly income, physical activity, eating habits, and a family history of prehypertension. Results: Sex was the strongest prehypertension predictor. Efforts should be directed at other modifiable risk factors, such as obesity and smoking, to reduce prehypertension risk. Screening for prehypertension and advocating lifestyle modifications in young people is highly recommended to decrease progression to hypertension.