Abstract: Studying the coupling and coordination relationship between ecological protection and high-quality economic development is conducive to providing a scientific basis for the green and sustainable economic development within river basins. Based on the data from 2019 to 2023 of three counties and one district in Wuwei City within the Shiyang River Basin, this study constructed a comprehensive evaluation system for the coupling and coordination of ecological protection and high-quality economic development. Guided by the theories of sustainable development and coupling coordination, it adopted the entropy weight method, coupling coordination degree model, and relative development degree model to conduct an in-depth analysis of the coupling and coordination relationship between the two systems in the basin and their spatiotemporal evolution characteristics. The results show that: The coupling coordination degree of the two subsystems in the Shiyang River Basin generally showed an upward trend over time. The coordination degree in the upper reaches was higher than that in the lower reaches, while the middle reaches, with concentrated economic development activities and high environmental pressure, faced significant challenges in the coordinated development of the two systems. Spatially, the coupling coordination degree between the two systems in the basin exhibited the problem of unbalanced and inadequate development among different regions, characterized by a slow improvement rate and spatial imbalance. On the whole, the relative development type of the basin showed a trend where ecological protection lagged behind the high-quality economic development, and the spatial distribution of the relative development types in various counties and districts presented an unbalanced feature.