Hypertension is a major risk factor for heart disease, stroke, kidney failure, and premature death. In Saudi Arabia, studies looking at the prevalence of hypertension in young adults are scarce. We aim to provide current data on the prevalence and associated risk factors of hypertension in young adults to allow us to assess the magnitude of the problem in this age group and suggest the appropriate recommendations to physicians and policymakers. The objective of the study is to assess the prevalence of hypertension and its associated risk factors in medical students attending the College of Medicine in Qassim University, Qassim, Saudi Arabia. It is a cross-sectional study that was conducted during the year 2017 on medical students attending the College of Medicine at Qassim University. A total of 130 students were selected using multistage stratified random sampling. We collected data on sociodemographic information and risk factors using a self-administered questionnaire derived from the WHO STEPS instrument, and we measured the blood pressure and body mass index (BMI) of the participants. Data were analyzed using Statistical Package for Social Sciences version 23.0. The prevalence of hypertension in the study sample was found to be 14.6%, 6.9% of which had isolated diastolic hypertension while 4.6% had isolated systolic hypertension, and the remaining 3.1% had systolic-diastolic hypertension. The prevalence of prehypertension was found to be 29.2%. Only 21.1% of the participants found to be hypertensive were diagnosed and on antihypertensive therapy. We found a significant association between gender, BMI, and history of diabetes and hypertension. Our study confirms the notion that there are high rates of prehypertension and hypertension among young adults, the majority of which are undiagnosed cases. This calls for the need of a comprehensive national screening program and campaigns that increase awareness about hypertension and its associated risk factors.