The present study examined differences in lifetime use and initiation of substance use and associated risk factors for alcohol, cigarettes, and marijuana among seven subgroups of Asian American (AA) adolescents: Chinese, Filipino, Indian, Japanese, Korean, Vietnamese, and Mixed heritage Asian. Sixth and 7th grade AA adolescents in Southern California were surveyed five times over three academic years. We examined subgroup differences in (1) lifetime alcohol, cigarette, and marijuana use assessed at baseline, (2) initiation of each substance over three years, and (3) baseline individual (positive and negative expectancies about substances, resistance self-efficacy, and intentions to use), family (closest adult and older sibling substance use), and school factors (perceived peer use). Although there was considerable heterogeneity in lifetime substance use and initiation rates, subgroup differences were not statistically significant (ps > .20). Significant subgroup differences existed for negative expectancies about use, perceived peer use, and close adult alcohol and cigarette use (ps < .05). Specifically, Vietnamese and Japanese adolescents had the lowest negative expectancies about cigarettes and marijuana, respectively. Vietnamese adolescents reported the highest levels of perceived peer cigarette use. Mixed-heritage adolescents reported the highest frequency of alcohol and cigarette use by their closest adult. Although no differences in substance use rates were observed, these findings are an important first step in understanding heterogeneity in AA adolescents' risk for substance use and initiation.