Abstract: Xi Ujimqin area is located in the Xilin Gol grassland, Inner Mongolia, where is heavily covered, with less outcrops and complicated geological conditions. It is difficult to carry out normal geological survey in the area. With analysis on the geophysical fields of the area, it is divided into sub-areas by different types of characters, which represent various geologic features. The distributions of geologic bodies, as well as faults and volcanic apparatus, are inferred and interpreted based on the characteristics of the geophysical fields.