ABSTRACT
Humans display ingroup favouritism when trusting others, showing greater trust toward ingroup members than outgroup members. This research examined regional differences in intergroup trust between southern and northern China. In Study 1, we analysed data from a national survey (N = 10,968) to compare attitudes toward trust in various relationships among respondents from the North and South. In Study 2, we used game experiments (N = 156) to measure behavioural trust among northern and southern college students toward different groups, and to explore micro-level explanatory factors for regional differences. Study 3 (N = 65) further tested the mechanisms underlying these regional differences through experimental manipulations based on the results of Study 2. The findings indicated that both southerners and northerners exhibit ingroup favouritism under relational cues, while only northerners show ingroup favouritism under categorical cues. Expectations of reciprocity can explain the regional differences in intergroup trust between South China and North China. This research provides new insights and evidence on the cultural differences in intergroup trust, thereby enhancing the understanding of regional culture and its psychological manifestations in China.