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In order to evaluate the quality of plough horizon in dry farming region of Northeast China, the principal component analysis (PCA) was used to establish the minimum data set (MDS), and the characteristics of plough horizon quality were indicated by using the MDS-Plough horizon integrated quality index (MDS-PHIQI). In addition, the regional classification of soil samples was studied based on systematic cluster analysis, and the negative factors of plough horizon quality were identified by obstacle factor diagnosis model. The results showed that the MDS suitable for use in the assessment of plough horizon quality for study area included such indicators as soil organic matter (SOM)content, total nitrogen (TN) content, available phosphorus (AP)content, clay particle content, plough layer penetration resistance (PLP) and compacted layer thickness (CLT). The MDS can replace the total data set to evaluate the quality of plough horizon in dry farming region of Northeast China. The quality index of plough horizon in study area was between 0.10 and 0.53, with an average value of 0.30, which was at medium and low levels. From the perspective of fertilizer conservation and yield-increasing potential, the suitability thresholds of those diagnostic parameters for reasonable plough horizon of dry farming region of Northeast China were indicated as follows: soil organic matter content of greater than or equaled 37.16g/kg, total nitrogen content of greater than or equaled 1.75g/kg, the clay particle content of 4.60%~6.19%, available phosphorus content of greater than or equaled 26.38mg/kg, the plough layer penetration resistance of less than or equaled 364.56kPa, and the compacted layer thickness of less than or equaled 8.18cm. In the research, geographic areas can be characterized as high, medium or and low levels of grain yields. Different types of barrier factors for plough horizon in the study area can be divided into plough horizon structure barriers (low grain yield areas), comprehensive barriers of structure and soil fertility constraints (medium grain yield areas), and soil fertility constraints (high grain yield areas). Viewed as a whole, the main obstacles to the improvement of the quality of plough horizon were penetration resistance of plough layer, total nitrogen content, and soil organic matter content, appropriate tillage and fertilization measures should be taken in view of the above three obstacle factors. The research can provide theoretical basis and parameters for the evaluation of plough horizon quality and the construction of reasonable plough horizon in dry farming region of Northeast China.