The Babao River Basin is the upstream region of the Heihe River which is the second largest inland river basin in the arid regions of northwest China. To monitor the characteristics of space-time of the eco-hydrological processes in the Babao River Basin, this paper discussed a regression kriging modelbased sampling optimization method. Land surface temperature, as one of eco-hydrological variables in the Babao River Basin, has been exemplified. The experiment results demonstrate that this sampling optimization method can consider the relationship of target variable and environmental variables and the spatial autocorrelation of regression residuals to obtain the optimization design in the geographic space and attribute space simultaneously. The optimized WSN is more efficient to capture the temporal and spatial variations of the eco-hydrological variables for monitoring the eco-hydrology process in the Babao River Basin.