Abstract: Zhengzhou, a typical transportation-hub city, was selected as the research area. Based on the long-term Landsat image data, a Remote Sensing Ecological Index (RSEI) was constructed to dynamically monitor and evaluate the ecological environment quality of Zhengzhou. The results show that the ecological environment quality of Zhengzhou City has significantly improved in the past 20 years, the RSEI value has risen from 0.356 in 2000 to 0.428 in 2020, and the main factors affecting the rise of the RSEI value are surface humidity and surface temperature. Besides, the shift of spatial gravity centers shows that the good-and-excellent-grade gravity centers in the RSEI index move to the city’s northwest, gradually approaching important transportation hub nodes such as railway stations, high-speed railway stations, and airports, which shows that the high-quality coordinated development of Zhengzhou’s transportation-hub-city construction and ecological protection has promoted the further improvement of the local ecological environment quality.