China is suffering from serious air pollution. Regional air quality varies significantly due to intensive inter-provincial trades, diversified resource endowments and complicated economic structures. This study breaks the limitations of measuring environmental inequality only from a single perspective and establishes a three-perspective atmospheric pollutant equivalents accounting model (or APE accounting model) for air-pollution inequality assessment under environmentally-extend multi-regional input-output framework. From three perspectives of local production (i.e. production-based), final demand (i.e. consumption-based) and primary supply (i.e. income-based), APE emissions, APE transfers and environmental Gini coefficient are investigated to exam emission responsibilities of various impact factors, evaluate the impacts of inter-provincial trades on pollutants transfers, and characterize regional emission inequalities at both provincial and sectoral levels. The results indicate that local emitters are merely parts of contributors to air pollution. Direct emitters like Hebei Province, primary suppliers like Inner Mongolia and final consumers like Shandong Province induce large amounts of air pollutants as embedded within various economic activities. Because of unequal supply-demand levels and complex exchange mechanisms, three-perspective APE emissions are significantly heterogeneous, especially in mining, construction, energy and material-transformation sectors. Particularly, inequality of the mining sector in embodied emissions has the highest environmental Gini coefficient (0.881). This model provides a framework to assess regional environmental inequality and its findings provide scientific bases for the formulation of desired regional air pollution control policies.