Abstract: The Beliqutai-Bayanbulag Area is located within the Erlian Basin metallogenic province and exhibits favorable uranium metallogenic conditions. However, the area is extensively covered by basalt, and the tectonic unit divisions, as well as the distribution and characteristics of the target sand bodies for prospecting, remain unclear, which has become a bottleneck constraining uranium exploration breakthroughs in the region. In this study, the audio-frequency magnetotelluric（AMT） method is applied, and the AMT profile data are inverted using SCS2D software. This effectively reveals the geoelectrical structure of the basalt-covered area and determined the burial depth and spatial distribution characteristics of the sand bodies in the lower member of the Lower Cretaceous Saihan Formation. The burial depths of the sand bodies range from 115 m to 400 m, with thicknesses between 45 m and 300 m, mainly concentrated in the Hongger Depression and the southern branch of the Chaokewula Depression. Based on electrical characteristics, 15 fracture structures are further inferred, and the boundaries of structural units as well as the caprock structures are identified. Drilling validation results show that the interpreted burial depths and thicknesses of the sand bodies are generally consistent with the drilling data, providing a reference and basis for sandstone-type uranium exploration in the Erlian Basin.