Background: Diet plays a crucial role in the regulation of chronic inflammation. The sparse evidence available in adult populations indicates that diet quality is linked to the dietary inflammatory potential; however, this association has not been established in youth. Design: Data were obtained from a representative national sample of 2889 children and young people in Spain, aged 6-24 years. The dietary inflammatory potential was measured by the dietary inflammatory index (DII), and diet quality by three conceptually different measures: the Mediterranean Diet Quality Index for children and adolescents (KIDMED), energy density, and total dietary antioxidants capacity. Results: The mean DII was 1.96 ± 0.76 units Scoring for the KIDMED index and the total dietary antioxidant capacity significantly decreased (p < 0.001 and p = 0.030, respectively) across quintiles of the DII, whereas the opposite was true for energy density (p < 0.001). The effect size of these associations was strongest for energy density, followed by the KIDMED index and total dietary antioxidant capacity. Conclusion: A healthy diet characterized by high adherence to the Mediterranean diet, high total dietary antioxidant capacity, or low energy density was linked to greater anti-inflammatory potential of the diet, as measured by the DII.