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In order to explore the structure characteristics of topsoil in dry farming region of Huang-Huai-Hai, geostatistics and Mann-Kendall test methods were used to identify the position and thickness of plough layer and compacted layer in the dry farming region based on the data of soil penetration resistance, and the spatial variation characteristics and influencing factors of the plough layer and compacted layer were explored. The results showed that soil bulk density, water content and soil texture were the main influencing factors of penetration resistance. Compared with topsoil, penetration resistance of deeper soil was more affected by water content and organic matter content. There was a compacted layer in the soil profile in the study areas and the spatial variability of the compacted layer was heterogeneous. The area of thicker compacted layer was mainly concentrated in the northern of Anhui Province, with an average thickness of 12.38cm,，and Henan Province had a relatively thick tillage layer, with an average thickness of 19.31cm. In addition to natural factors, agricultural mechanical tillage was an important factor affecting the thickness and penetration resistance of soil compacted layer and plough layer. The high total power area of agricultural machinery presented the characteristics of thinner tillage layer, thicker compaction layer and larger penetration resistance.