Sexual-minority college students continue to experience heterosexism in the form of heterosexist and biased language from peers. Religion has been identified as a predictor of sexual prejudice among college students. Yet there is limited research on the intersection of race, religion, and heterosexism, and on interventions designed to address this prejudice. This study examined the effectiveness of multicultural education courses at a large public university on reducing heterosexism in Christian students. Analysis of pre- and post- data using repeated measures ANCOVA indicated African American Christian students had significantly higher heterosexism scores than White Christian students, and African American Christian students had a significant decrease in heterosexism as compared to White Christian students after taking a service learning course. These results have implications for future research and education on prejudice reduction.