Abstract: The Uliji Area of the Bayingobi Basin has superior uranium mineralization conditions, but the Quaternary System covers a wide range, and the distribution characteristics of structural units and target sand bodies are unclear. Moreover, the scale of the geological map is currently too small, and the distribution of structural units in the study area is not yet clear, making it difficult to meet the needs of uranium exploration. By conducting controllable source audio magnetotelluric surveys（CSAMT）, the electrical structure of the sedimentary cover layer is obtained, and the spatial distribution characteristics of the target sand body are inferred, mainly distributed in the Uliji and Tolai Depressions, with a burial depth of 60-330 m and a thickness of 50-340 m. A new division has been made for the structural units in the research area, which is a structural framework of “two depressions sandwiched with a convex”, with faults controlling the boundaries of the structural units. Through on-site geological surveys and subsequent drilling verification, the accuracy of the interpretation results has been proven, providing reference for the exploration of sandstone type uranium deposits in relevant regions.