Affective polarization amplifies hostility toward out-groups, eroding social trust and threatening the sustainability of democratic communities. As South Korean society accelerates its transition toward multiculturalism, it faces increasing risks of affective polarization surrounding migrants. In this context, this study examines the role of journalistic media and explores how news frames about migrant workers influence affective polarization through the mediation of discrete emotions (anger, hope, and sympathy). Specifically, an experimental design (N = 256) was employed to analyze the differential effects of alternative frames (human rights violation frame, economic benefit frame, and diversity inclusion frame) compared to the threat frame. The main findings are as follows. First, the threat frame, human rights violation frame, and economic benefit frame significantly strengthened their corresponding perceptions (threat perception, discrimination perception, and economic contribution perception, respectively), while the diversity inclusion frame did not affect inclusive perception. Second, no direct effects of news frames on emotions were observed; however, an indirect pathway through perceptions of migrant workers was identified. Third, compared to the threat frame, all three alternative frames reduced anger, thereby indirectly mitigating affective polarization toward migrant workers. Based on these findings, implications for news reporting practices are discussed.