OBJECTIVE This study examines the prevalence of disordered eating behaviors (DEB) and its associations with glycemic control, insulin sensitivity (IS), and psychosocial functioning in a large, diverse cohort of youth and young adults with type 1 or type 2 diabetes. RESEARCH DESIGN AND METHODS In the SEARCH for Diabetes in Youth study, 2,156 youth and young adults with type 1 diabetes (mean ± SD age 17.7 ± 4.3 years; 50.0% female) and 149 youth and young adults with type 2 diabetes (age 21.8 years ± 3.5; 64.4% female) who were receiving insulin therapy completed the Diabetes Eating Problem Survey–Revised (DEPS-R), a self-reported measure for identifying disordered eating. DEB were defined as a DEPS-R score ≥20. Demographic characteristics, clinical measures, and health behaviors of participants with DEB and those without DEB were compared by using t tests. RESULTS DEB were observed in 21.2% of participants with type 1 diabetes and 50.3% of participants with type 2 diabetes. Participants encountered challenges in maintaining a healthy weight while controlling their diabetes. For both types of diabetes, individuals with DEB had a significantly higher BMI z score, lower insulin sensitivity, more depressive symptoms, and poorer quality of life than those without DEB. Diabetic ketoacidosis episodes occurred more frequently in youth with type 1 diabetes with DEB compared to those without DEB. CONCLUSIONS These findings highlight that DEB are prevalent among youth and young adults with type 1 and type 2 diabetes and who are receiving insulin therapy, and DEB are associated with poorer clinical outcomes and psychosocial well-being. Heightened awareness and early interventions are needed to address DEB for this at-risk population, as are longitudinal studies evaluating the course of DEB and diabetes outcomes.