What shapes preferences for income redistribution? Studies find that social identification plays an important role. In this paper, I argue that in-group favoritism generated through income proximity and out-group discrimination stemming from a nation/foreigner cleavage affect redistribution preference. Using data from a survey experiment with 4,002 Japanese citizens, I examined whether priming the poor as recipients of public assistance (or Seikatsu Hogo) generates more (less) support for income redistribution among the poor (the wealthier) and whether priming foreigners as public assistance recipients decreases support for redistribution. Analyses reveal that respondents with annual household income of 5–10 million yen negatively respond to the treatment priming the poor as public assistance recipients. Results also indicate that priming foreigners as public assistance recipients decreases support for redistribution. These findings corroborate previous research that finds evidence from North America and Europe. Analyzing a sample from Japan offers the external validity because the recent rise in income disparity in Japan involves unique characteristics including pauperization of low-income groups without enriching the wealthy. A rapid increase in the inflow of immigrants to Japan necessitates the need to study how Japanese people shape their redistribution preference in response to a growing number of foreign residents.