People may perceive economic inequality through moral lens, focusing on the unfair distribution of resources, or as a threat to their personal and social environment. This research examines how justice- and threat-based concerns shape reactions to economic inequality. In Study 1 (N = 358), we identify elements of inequality perceived as unjust or threatening and explore how these are organized into meaningful clusters using network analysis. We identified four overarching concerns: distributive justice, social harmony, inequality of opportunities and economic threats. Distributive justice and social harmony concerns were the most prominent, associated with perceptions of injustice and threat, respectively. Study 2 (N = 260) showed that distributive justice (but not social harmony) concerns were positively associated with collective action and support for redistribution. In Study 3 (N = 1536), perceived economic inequality was positively related to both concerns, but only distributive justice concerns consistently mediated the relationship between perceived economic inequality and support for measures to reduce inequality. In Study 4 (N = 214) exposure to distributive justice concerns, compared to social harmony and control conditions, increased support for taxing the rich and assisting the poor. Results suggest that framing economic inequality as a justice issue effectively promotes social change.