There are some research difficulties and highlights in analyzing spatial variation in recent years, such as how to choose advanced methods, how to make efficient and reasonable experimental designs, how to normalize field sampling program process, and how to select representative sampling points. In view of the above mentioned issues, a research on spatial variable of soil thermal parameters on basin scale in Jinghui Canal Irrigation District, Shaanxi Province was conducted by combining RS, GPS and GIS technology. The results showed that soil thermal capacity, thermal diffusion and thermal conductivity displayed moderate variation in the selected regional scale. Thermal diffusion and thermal conductivity displayed a stronger spatial heterogeneity than soil thermal capacity, which showed a relative weaker one. Furthermore, a strong spatial dependence was found among the above three parameters. The optimum fitting models for soil thermal capacity, thermal diffusion and thermal conductivity were exponential model, spherical model and Gaussian model, respectively. And the sample spacings of above three models were recommended to be 2.67, 3.68 and 2.76km, respectively. Meanwhile, the best sampling spacing of soil thermal parameters in this region was recommended to be 3km. A simple fitting formula for soil thermal parameters determined by basic parameters of soil physics was established based on describing the spatial variability of soil thermal parameters. It was proved to be a good applicability with R2>0.80 after verifying. It indicated that quantization analysis on complex spatial variability of soil thermal parameters could be well achieved based on the introduced method.