Afforestation is an important aspect of ecosystem restoration (ER) and poverty alleviation (PA) through direct and indirect social, economic, and environmental effects. However, the existing afforestation projects worldwide have mainly viewed economic benefits through the narrow lens of subsistence and livelihood, thereby underestimating both indirect PA and the associated negative effects on agricultural production when formulating long-term solutions to global poverty. This study aimed to systematically examine the ecological, agricultural, and economic effects of ecosystem restoration in southeastern China over four decades based on biophysical models and statistical records, and further proposed an upgraded strategy for sustainable PA through ER that addresses conservation objectives and resource needs. We found that ER promoted vegetation growth and enhanced carbon sequestration and soil retention. Meanwhile, industrial transformation improved the economic scale and livelihood diversity (i.e., disposable income), which alleviated poverty and improved social services and infrastructure conditions. Nevertheless, the secondary and tertiary industries gradually replaced the primary industry in terms of output, and increased animal husbandry and forestry development weakened crop planting. Planting structure adjustments further threatened the stability of the grain supply, particularly after 1999, which could potentially lead to a grain crisis. Therefore, we propose upgraded forest management and coordinated development policies to avoid a grain crisis, improve livelihood diversity, balance multidimensional benefits, and facilitate sustainable development. Study results serve as a valuable reference for policy formulation and ER measures for more inclusive, resilient, and sustainable PA.