Given that income disparity is expanding and diet-related environmental footprints are increasing in urban China, this study aims to investigate the heterogeneity in these footprints across various income classes and examine the effect of income distribution on the total environmental footprints. Based on the quadratic almost ideal demand system model and taking into consideration the problems of endogeneity of food expenditure and zero expenditure, we estimate the income elasticities for 10 food categories across seven income classes and project the diet-related environmental footprints under seven scenarios for various strategies of the income distribution. The results show that per capita diet-related environmental footprints are greater for higher income classes than for lower income classes, as the former consume more animal-based food. Compared with high-income classes, income growth favouring low-income classes results in a rather significant increase in diet-related environmental footprints. With further economic growth, the lowest income group makes the greatest contribution to the increase in diet-related environmental footprints. Thus, policymakers should promote a more sustainable diet on the road to alleviating income inequality to ensure sustainable environmental development.