Abstract: Abstract: Basic soil productivity is an important indicator of soil production ability and it can ensure wheat yield stabilization for food security. The improvement of basic soil productivity can increase the production potential of farmland, increase the yield, control the amount of fertilizer in the appropriate range, reduce agricultural environmental pollution, and establish an environmental-friendly cropping pattern. Basic soil productivity can be characterized by crop yield without fertilization and has significant correlation with soil nutrients. Central and southern Hebei province is one of the main wheat producing areas in China. The analysis of yield nutrient influencing factors will benefit the soil fertility improvement and yield increasing in Hebei Province. Using 876 winter wheat demonstration field trails' data, which come from the national soil testing and fertilizer formulation project in Hebei province from 2006 to 2013, we studied the basic wheat yield and basic yield gaps distributions and analyzed the basic yield contribution rates. Soil fertility index including soil organic matter, available nitrogen, available phosphorus, available potassium and soil pH were selected as influencing factors of yield in this study. We quantified the contribution rates of each soil nutrient factor to the basic yield gap of soil productivity by using the boundary line analysis method. The result showed that the yield of basic soil productivity was between 1 080 and 7 404 kg/hm2 with an average of 4 573 kg/hm2. Compared with the maximum yield, the yield gap was from 69 to 6 324 kg/hm2 with the mean value of 2 831 kg/hm2. The average contribution rate of basic soil productivity was 71.1%. There was great potential to increase grain yield. The contribution rates of basic soil productivity were significantly positively correlated with the increase of basic yield. When the basic yield increased by 1 000 kg/hm2, the soil contribution rates increased by 8%. The increase of soil basic soil productivity led to the increase of contribution rates of basic soil productivity. Models were constructed by boundary line analysis to fit the relationships between soil nutrient factors and basic soil productivity. We found that the yield boundary point of the soil nutrient factors all had good fitting relationships. The pH simulation was quadratic curve, and soil organic matter, available nitrogen, available phosphorus and available potassium were quadratic platform curve. The soil organic matter had the highest contribution rate to the basis soil productivity yield gaps, which was 16.6%, followed by pH and available nitrogen with the contribution rate of 10.9% and 10.5%, respectively. The contribution rates of available potassium and available phosphorus were 4.1% and 2.9%, respectively. The results suggest that the soil organic matter, pH and available nitrogen may be the primary factors improving fertility in Hebei province. The boundary line analysis also showed that the soil nutrient factors of pH value 8.1, organic matter 24.6 g/kg, available nitrogen 120.6 mg/kg, available phosphorus 12.4 mg/kg and available potassium 89 mg/kg were suitable for obtaining high yield of winter wheat. The boundary line analysis can be used to analyze regional scale soil nutrient factors for yield limiting, and guide the direction of soil fertility improvement for increasing basic yield productivity.