Type 1 diabetes mellitus (T1DM) is the third most common chronic childhood disease in the United States. As more Hispanic and non-Hispanic black children are diagnosed with T1DM, racial and ethnic disparities in the treatment and outcomes of T1DM are increasing. This article reviews the increasing incidence and prevalence of T1DM in non-Hispanic white, non-Hispanic black, and Hispanic children. In addition, the racial and ethnic disparities in diabetes treatment, such as blood glucose monitoring, insulin therapy, and continuous glucose monitoring, and outcomes, including glycemic control, diabetic ketoacidosis, severe hypoglycemia, retinopathy, nephropathy, neuropathy, and diabetes-related mortality, are highlighted.