This article explores the association between intergenerational social mobility and attitudes towards income differences in post-socialist societies. I hypothesise that based on the psychological mechanism of self-serving bias in causal attribution, those who experience upward social mobility are more likely to support greater income differences, and that subjective intergenerational mobility has stronger association with attitudes towards income differences than objective mobility because individuals filter their objective environment in order to derive their subjective perceptions of the world and their own experiences. The described hypotheses are tested with two cross-national data sets – European Values Studies and Life in Transition Survey. The derived findings are robust to alternative statistical specifications and indicate that individuals who perceive themselves as subjectively mobile have significantly different attitudes towards income differences in comparison to non-mobile groups, but that this effect does not manifest among objectively mobile individuals.