Coupling of social, economic, and environmental systems are important for achieving the sustainable development. This article examined the impact of China’s Targeted Poverty Alleviation (TPA) strategy on the sustainable development in the poor areas of China (PAC) and found that both the economic and social systems have developed rapidly in the PAC during the TPA period and the implementation of TPA facilitates the couplings among the three subsystems in the PAC and improves their coordination degree, turning from imbalanced to coordinated development.