Pediatric primary hypertension is increasingly common, occurring in 5-10% of normal-weight children and up to 25% of children with obesity. It is a risk factor for adult cardiovascular and renal disease. But even during childhood, hypertension is associated with significant morbidity, including cognitive impairment and organ damage. In the heart and kidneys, this organ damage is characterized by thickened heart muscle (left ventricular hypertrophy) and spillage of protein in the urine (albuminuria). Obese children are also at risk for fatty liver disease. However, the cause of pediatric primary hypertension, the role of obesity, and the mechanisms behind heart and kidney injury are poorly understood. Due to these limitations, there are no first-line medications, and treatment is often inadequate. An altered renin-angiotensin system may cause primary hypertension and related organ damage. Evidence suggests uric acid, FGF23, klotho, and obesity play a role in renin-angiotensin system-mediated injury. An improved comprehension of the pathophysiology of pediatric primary hypertension could enhance clinical care by targeting treatment to the cause of disease and informing novel measurement of organ damage.