In this paper, the Wenquan of QTP area was taken as the research area, 58 soil profiles deeper than 1 m were surveyed, and the profile distribution patterns of clay contents with the largest coefficient of variation and its relationship with environmental variables such as climate, topography, vegetation and soil parent materials were analyzed. The results showed that sand content of the Wenquan area is the largest in soil particle composition, more than 800 g/kg, but the coefficient of variation of clay content is the largest. The profile distribution pattern of clay contents can be divided into four types, i.e., decreasing, increasing first then decreasing, decreasing first then increasing and irregular. The main controlling factors are slope, aspect and the cold season ground temperature for the decreasing pattern, the surface temperature for the increasing first then decreasing pattern, elevation, topographical humidity index and NDVI for the decreasing first then increasing pattern, and topographical humidity index, plane curvature and elevation for the irregular pattern. The above results indicated that the climate and topographic factors are the decisive factors affecting the profile distribution pattern of clay content in the Wenquan area of the QTP, which provides a scientific basis for studying the soil-landscape model and spatial distribution of soil texture in the QTP.