Identifying dietary factors associated with blood pressure (BP) in children and adolescents would help guide recommendations for prevention of elevated BP, which is a major public health problem. This paper reviews 46 reports of studies examining relationships between dietary nutrients and BP in children and adolescents, many of which studied more than one nutrient. Sodium is the most extensively studied nutrient, with 25 observational and 12 intervention studies identified. Although many studies suffer from methodological problems, the results suggest that higher sodium intake is related to higher BP in children and adolescents. The results of 13 observational and 2 intervention studies of potassium and BP do not provide a clear picture of a relationship. The results of 8 observational and 1 intervention study of calcium and BP are inconclusive. Five observational studies of magnesium and BP provide evidence of an inverse relationship, but no intervention studies were identified. Nine studies of macronutrients and food groups or dietary patterns are inconclusive. Additional research is needed to provide more information about the relationships between dietary nutrients and BP in children and adolescents. Recommendations are provided for methodological features of additional research on diet and BP in children and adolescents.