Abstract: Based on six-day data from 60 broadband seismic stations along two linear profiles deployed in the northern and southern Ordos Basin, we firstly used the HVSR (Horizontal-to-Vertical Spectral Ratio) method to image the thicknesses of the loess and sedimentary layers. Significant north-south differences in the loess were observed, where thickness varied smally around 60 m in the north, whereas it changed around 60 m in the two flanks and reached 80 km in the middle in the south. Sediment increases gradually from ~3 km to ~5 km from east to west in the north, and thickens from ~2 km to ~3 km slowly in the east part and increases from ~3 km to ~5 km fast in the west part in the south. We speculate, that the north-south difference in the loess layer are likely related to differences in geological evolution and sedimentary environments between the two and south. The east-west variation and different in the north and south parts in the sedimentary layers may be influenced by uneven sedimentation across different regions, as well as the westward tilting of the Ordos Basin and multiple uplift and erosion events since the Triassic. The loess and sedimentary layer features obtained in this study can provide the information for the analysis of paleoclimate and sedimentary characteristics and evolution process of Ordos Basin, and also supports the study for accurate imaging of deep structure of crust-mantle and risk assessment and related geological tectonics and earthquake disaster in this area.