Background: Elevated blood pressure, or hypertension, is one of the main health problems among adolescents globally. However, there are limited data on hypertension among adolescents in Sudan. This survey aimed to investigate the prevalence of elevated blood pressure/hypertension and associated factors among adolescents in Gadarif City, Sudan. Methods: A community-based cross-sectional survey was conducted during a three-month period (August to October 2023) in Gadarif City, Eastern Sudan. A face-to-face interview questionnaire was used to collect sociodemographic information. Adolescents’ anthropometric (weight and height) measurements were taken, and blood pressure was measured. Multivariate binary and linear regression analyses were performed to analyze the data. Results: A total of 384 adolescents (178 [46.4%] boys and 206 [53.6%] girls) were included in the study. The median (interquartile range, IQR) of the age was 14.0 (12.1–16.1) years, and that of the body mass index (BMI) was 16.9 (15.2–20.0) kg/m2. Thirty-four (8.9%) adolescents had hypertension/elevated blood pressure (≥95th percentile). After adjusting for confounders, multivariable binary regression analysis showed that age (adjusted odds ratio [AOR], 1.20; 95% confidence interval [CI], 1.03–1.42) and BMI (AOR, 1.12; 95% CI, 1.04–1.20) were associated with hypertension. Conclusion: Approximately one in ten adolescents in Eastern Sudan was hypertensive. Adolescents with higher age and BMI were at higher risk for hypertension. Maintaining a healthy BMI during adolescence is recommended to promote adolescents’ health.