In the United States, underrepresented racial minority (URM) students continue to face psychological barriers that undermine their achievement and fuel disparities in academic outcomes. In the current research, we tested whether a multicultural ideology intervention could improve URM students’ grade point averages (GPAs) during the first 2 years of college and thereby reduce the racial achievement gap. Specifically, first-year college students (N = 407) read a diversity statement that represented the schools’ diversity ideology in terms of either multiculturalism or colorblindness. URM students who read a multicultural diversity statement earned higher GPAs 2 years later compared to those who read a colorblind diversity statement. Furthermore, they earned higher GPAs compared to a nonparticipant campus-wide control group. The current study is the first to demonstrate that multiculturalism can increase the long-term academic outcomes of URM students in college.