To contribute to the pressing question of what drives individuals’ cross-cultural attitudes in our increasingly globalized world, in two studies, we examined the relationship between endorsement of polyculturalism (belief system focusing on historical and current interactions, influences, and connections among different racial/ethnic groups) and cross-cultural attitudes. In Study 1, high school and college students (N = 134) in the Philippines generally endorsed polyculturalism, and greater endorsement of polyculturalism was associated with more positive attitudes toward people from other countries living in the Philippines. In Study 2, college students, who were coming of age in two countries with richly diverse histories (Philippines: N = 168, United States: N = 211), generally endorsed polyculturalism, and in both countries, greater endorsement of polyculturalism was associated with more positive attitudes toward people from other countries and toward befriending people migrating from other countries. Across studies, polyculturalism explained unique variance in attitudes toward people from other countries after controlling for participants’ degree of national identification, social dominance orientation, and extent of positive feelings toward oneself. Implications of these findings are discussed.