International adoptees are highly heterogeneous in terms of their pre-adoption adversities and their post-adoption experiences, needs, and problems. The diversity among international adoptees poses a challenge related to adequately addressing their needs. The first aim of this study was to find subgroups of adult international adoptees based on common risk and protective factors using a latent class analysis. The second aim was to examine whether the identified subgroups differed in outcome variables such as life satisfaction and psychological adjustment. This study employed a secondary analysis of the data from the Fact-Finding Survey on Korean International Adoptees conducted by the Korea Institute for Health and Social Affairs. The results showed variations in the patterns and levels of perceived risk and protective factors reported by adoptees. The latent class analysis revealed a three-class solution: Moderate, Protective, and High-risk classes. Furthermore, a One-way ANCOVA analysis showed that the three classes differed meaningfully on psychological adjustment and life satisfaction scores. These findings highlight differences in levels of risk and protective factors and the need to develop appropriate interventions that can address the needs of South Korean adult international adoptees.