The study examined variation in the prediction of adjustment in Taiwanese students by ethnic density. A total of 155 Taiwanese students were assessed via survey pre-departure and three times post-arrival in the United States. Hierarchical regression analysis showed students on campuses with fewer other Taiwanese peers formed more friendships with Americans and developed greater English competence by the second semester than those on campuses with more Taiwanese students. Furthermore, homesickness, affiliation with Americans, and English competence in the second semester predicted functional adjustment in the third semester among students at moderate ethnic density schools, while baseline English competence alone predicted adjustment in students on high ethnic density campuses. Implications for facilitating cross-cultural adjustment are discussed.