With the increasing burden of noncommunicable disease, adolescence is viewed as an opportune time to prevent the onset of certain behaviors and promote healthy states. Although adolescents comprise a considerable portion of Saudi Arabia's population, they have received insufficient attention and indicators of their health status, as a first step in a prevention cycle are unavailable. This study was carried out with the aim of identifying the health risk behaviors and health status of adolescents in Saudi Arabia. This cross-sectional, school-based study was carried out in all 13 regions of Saudi Arabia. Through multistage, cluster, random sampling, intermediate, and secondary school students were invited to participate. Data were collected by means of a self-administered questionnaire addressing health risk behaviors and health status, clinical anthropometric measurements, and laboratory investigations. A total of 12,575 adolescents participated. Various health risk behaviors, including dietary and sedentary behaviors, lack of safety measures, tobacco use, bullying, and violence were highly prevalent. Twenty-eight percent of adolescents reported having a chronic health condition, 14.3% reported having symptoms suggestive of depression, 30.0% were overweight/obese, and 95.6% were vitamin D deficient. Behaviors and conditions known to persist into adulthood and result in morbidity and premature mortality are prevalent among adolescents in Saudi Arabia. Preventive measures and local health policies are urgently needed and can impact adolescents and future adults. Establishing adolescent health surveillance is necessary to monitor trends and impacts of such measures.