Despite prior studies documenting learning difficulties among internationally adopted youth (IAY), none has explored academic motivation within this population. The current study addressed this gap by examining expectancies for success and task values in math and science among internationally adopted, domestically adopted, and nonadopted high-school students. Differences in students' math achievement and parents' beliefs about their ability were also explored. A subsample of 7,420 11th-grade students was selected from the "High School Longitudinal Study" data set (Ingels et al., 2011). After controlling for prior motivation, achievement, demographics, and clustering, analyses revealed that IAY held less adaptive motivational beliefs in math. Compared with their nonadopted peers, internationally adopted students reported lower expectancies for success, attainment value, and intrinsic value in math. Few differences in science motivation emerged, and no differences in math achievement were observed.