Abstract:The carbon and water use efficiency of vegetation is an important indicator to characterize the carbon-water cycle. In this study, we calculated the vegetation carbon use efficiency (CUE) and water use efficiency (WUE) based on the MODIS products from the Google Earth Engine (GEE) platform. The methods of trend analysis, coefficient of variation, R/S analysis, and partial correlation were used to study the spatiotemporal variations of the CUE and WUE of the Yellow River Basin from 2000 to 2020, as well as how they correlate with temperature and precipitation. The findings show that:(1) In the past 2 decades, the average annual CUE and WUE were 0.61 and 0.68 gC m-2 mm-1 in the Yellow River Basin; the vegetation CUE showed a non-significant decreasing trend, while the WUE showed a non-significant increasing trend. (2) Spatially, the vegetation CUE showed a trend of high in the west and low in the east, while WUE was the opposite. For different land cover types, the values of CUE descended in the order of grassland > cropland > shrub > forest; whereas the values of WUE descended in the order of cropland > forest > grassland > shrub. (3) Generally, the vegetation CUE of vegetation in the Yellow River Basin was negatively correlated with temperature and positively correlated with precipitation. The WUE was positively correlated with both temperature and precipitation in the northern Yellow River Basin, and it was negatively correlated with precipitation in the southwestern Yellow River Basin. (4) Among different land use types, the CUEs of grassland, forest, and cropland were mainly negatively correlated with temperature, and the CUE of shrubs was mainly positively correlated with temperature. The grassland CUE was positively correlated with precipitation in the northwest Loess Plateau, while showed a negative relationship in the source region of the Yellow River; for croplands, CUE was positively correlation with precipitation. (5) The relationships between the WUE and hydrothermal factor had strong spatial heterogeneity. Precipitation was the dominant factor affecting grassland WUE in the arid and semi-arid regions, while grassland WUE had negative correlations with both temperature and precipitation in the alpine regions; for shrubs, the WUE had negative correlations with temperature and positive correlations with precipitation; and farmland WUE had positive correlations with temperature due to the influence of human activities. The research results provide significant information for understanding the vegetation carbon-water coupling mechanism in the Yellow River Basin under the background of vegetation restoration and climate change.