Abstract: Based on fractal theory and patch shape index, scale/frequency relations of soil patches in Sangong River Basin were quantitatively analyzed. By combining soil patch area/perimeter fractal dimensions and shape index, soil type spatial distribution complexity in Sangong River Basin were discussed. Results show clear scale/frequency relations and area/perimeter relations of the soil patches in Sangong River Basin. Fractal dimensions of the soil types differ substantially in the basin. The highest fractal dimension is in alluvial soils and the lowest in meadow soloncha soils. There is significant correlation between complexity index and fractal dimension or patch shape index. The complexity index largely reflects the spatial distribution complexity of the soils. The most complex spatial distribution is in the alpine desert soils (K=2.403) and the simplest in semi-fixed aeolian soils (K=1.259).