OBJECTIVE: Given limited reports on diabetes among U.S. Asian and Pacific Islander youth, we describe the clinical characteristics, incidence, and prevalence of diabetes among Asian, Pacific Islander, and mixed Asian-Pacific Islander youth. RESEARCH DESIGN AND METHODS: Data were collected from 245 Asian, Pacific Islander, and Asian-Pacific Islander participants in the SEARCH for Diabetes in Youth Study, a population-based study of diabetes in youth (aged <20 years). Additionally, we estimated the incidence and prevalence of type 1 and type 2 diabetes for Asian, Pacific Islander, and Asian-Pacific Islander youth combined. RESULTS: Most participants with type 2 diabetes were obese (range Asian 71% to Pacific Islander 100%) with mean BMI >33 kg/m(2). In those with type 1 diabetes, Pacific Islanders were more likely to be obese, with a mean BMI of 26 vs. 20 kg/m(2) for Asian and Asian-Pacific Islander youth (P < 0.0001). The incidence of type 1 diabetes for youth aged 0-9 years was 6.4 per 100,000 person-years and 7.4 per 100,000 person-years for youth aged 10-19 years. The incidence of type 2 diabetes was 12.1 per 100,000 person-years for youth aged 10-19 years. CONCLUSIONS: While Asian and Asian-Pacific Islanders with type 1 and type 2 diabetes had lower mean BMIs than Pacific Islanders, all Asian, Pacific Islander, and Asian-Pacific Islanders with type 2 diabetes had mean BMIs above adult ethnicity-specific definitions of obesity. While the majority of Asian, Pacific Islander, and Asian-Pacific Islander youth had type 1 diabetes, older Asian, Pacific Islander, and Asian-Pacific Islander youth (aged 10-19 years) have an incidence of type 2 diabetes almost double that of type 1 diabetes. Public health efforts to prevent type 2 diabetes and obesity in Asian, Pacific Islander, and Asian-Pacific Islander adolescents are needed.