Renewable energy technologies are typically material-intensive in terms of the manufacturing and construction of the infrastructure. In particular, wind power needs a huge foundation and three long blades on a high tower to capture and convert wind energy into electricity. Wind power development in China has been soaring, and the sector has inherited regional disparities. Therefore, an analysis of the material efficiency of the country's wind power infrastructure system in a spatially and temporally explicit manner will contribute to the green transition of wind power in China. In this study, a bottom-up material flow analysis model and efficiency indicators, including the averaged material intensity (AMI) and the material stock efficiency (MSE), are developed using high-resolution material inventory data to quantify the material in-use stock of China's wind power sector from 1989 to 2018. The results show that the total material stock of China's wind power sector reached 172.2 Mt by the end of 2018, and the dominant materials were concrete (85.9%) and steel (17.9%). The AMI decreased from 1615 t/MW in 1989 to 736 t/MW in 2018, presenting a notable dematerialization trend, along with a periodic upgrade in wind turbine sizes. The MSE showed significant spatial disparities, ranging from 35 MWh/kg in Gansu to 66 MWh/kg in Fujian in 2018. Strategies to enhance the material efficiency associated with deploying wind power in China include the design and manufacturing of larger wind turbines, balancing the disparity between production and demand, and coordinating policies between central and local governments to reduce curtailment.