Although immigrant integration policies have long been hypothesized to be associated with majority members’ anti-immigrant sentiments, systematic empirical research exploring this relationship is largely absent. To address this gap in the literature, the present research takes a cross-national perspective. Drawing from theory and research on group conflict and intergroup norms, we conduct two studies to examine whether preexisting integration policies that are more permissive promote or impede majority group members’ subsequent negative attitudes regarding immigrants. For several Western and Eastern European countries, we link country-level information on immigrant integration policies from 2006 with individual-level survey data from the Eurobarometer 71.3 collected in 2009 (Study 1) and from the fourth wave of the European Value Study collected between 2008 and 2009 (Study 2). For both studies, the results from multilevel regression models demonstrate that immigrant integration policies that are more permissive are associated with decreased perceptions of group threat from immigrants. These findings suggest that immigrant integration policies are of key importance in improving majority members’ attitudes regarding immigrants, which is widely considered desirable in modern immigrant-receiving societies.