Racial and ethnic health disparities in primary care have been well documented in the US healthcare system. However, very little attention has been directed toward inequities in child health. The aim of this review is to provide context for the scope of the challenges associated with addressing pediatric health disparities in primary care by comparing the weight of evidence regarding racial/ethnic health disparities for children vs adults. A multisystem health disparities conceptual model will frame the search strategy and analysis of the review. This paper will: (1) identify knowledge deficits in the understanding of existing disparities in pediatric primary care relative to adult primary care; (2) assess root causes of disparities for children vs adults; and (3) propose recommendations for a research agenda and policy implementation to eliminate disparities in pediatric primary care.