Objective: There are many studies on hypertension in middle-aged or older athletes, however few studies in young athletes are reported. The purpose of this study is to clarify the factors related to hypertension in young athletes. Design and Methods: The subjects are 256 young male athletes (18.3 ± 1.0 years) of the College of Physical Education. Physiological measurement data and blood samples as fasting status were collected at the time of admission by medical checkup. Muscle mass was evaluated by bioelectrical impedance. Results: Mean height was 172.0 ± 6.4 cm, body weight (BW) 69.3 ± 11.8 kg, body mass index (BMI) 23.4 ± 3.3 kg/m2, systolic blood pressure (SBP) 123.8 ± 12.0 mmHg, and diastolic blood pressure (DBP) 63.4 ± 8.5 mmHg. Using the severity classification of the Japanese Society of Hypertension Guidelines 2019, there were 83 normal blood pressure (BP), 74 high normal BP, 91 elevated BP, 7 grade I hypertension, and grade II hypertension or higher were not present. We investigated correlations between physiological, laboratory parameters and blood pressure (BP). SBP had significant correlations with body surface area (p < 0.001), height (p < 0.01), weight (p < 0.0001), BMI (p < 0.0001), muscle mass (p < 0.0001), Heart Rate (HR) (p < 0.0001), Red blood cell (p < 0.05), and uric acid (p < 0.01). SBP showed no significant correlations with LDL-cholesterol, hemoglobin, fasting blood glucose, AST, ALT, Cr, eGFR. Multiple regression analysis showed that only BW and HR were significantly associated with SBP (y = 89.63 + 0.329 × BW + 0.16 × HR, p < 0.0001). Blood pressure in young athletes is associated with body weight. Strength-trained athletes such as judo are heavier than endurance trained athletes, and tend to have a high percentage of people with high blood pressure. Subsequent years of strength-trained exercise can lead to hypertension. Conclusions: Prehypertension and hypertension in young athletes are more strongly associated with body weight than lipids and blood glucose levels. The type of sport, strength-trained or endurance-trained, may affect the development of hypertension.