Abstract:【Objective】The large-scale production of mulberry requires sustainable nutrient management practices. However, the boron nutrition status of mulberry orchards in China remains sparsely explored. Thus, to set national standards, this study focuses on the boron nutrition status of mulberry orchards in China, aiming to provide scientific basis and technical support for constructing a national-scale boron nutrition management system.【Method】Taking Chinese mulberry orchards as the research object, this study explores the spatial differentiation of soil available boron (SAB) and total boron in mulberry leaves (PBC), as well as the correlation between SAB and major soil chemical indicators.【Result】The results showed that: (1) Soil SAB in Chinese mulberry orchards was significantly affected by region, soil depth, and their interaction. The order of SAB content among regions from high to low was Northwest > North China > East China > Southwest > Central South. The SAB content in the surface layer was slightly higher than that in the subsurface layer, with an overall average content lower than 0.50 mg·kg-1, belonging to a low content level. (2) Nearly 90% of mulberry orchards in China are distributed in the Central South, Southwest, and East China regions, facing the risk of boron deficiency, while the northern sericulture areas with relatively smaller mulberry orchard areas are at risk of boron toxicity. (3) Under the condition of low SAB soil, the average PBC of mulberry varieties across the country was 44.31 mg·kg-1. Among them, the PBC of mulberry varieties in Northwest mulberry orchards was significantly higher than that in other regions, reaching 60.51 mg·kg-1, while there was no significant difference in PBC among mulberry orchards in other regions. (4) Soil pH, available potassium (AK), available sulfur (AS), and exchangeable calcium (ExCa) were significantly positively correlated with SAB, while soil organic matter (SOM), total nitrogen (TN), and available phosphorus (AP) were significantly negatively correlated with SAB. (5) The contribution of major soil chemical indicators to the variance of SAB was in the order of pH > AK > AS > ExCa > SOM > TN > AP. Among them, pH contributed 19.18% to the variance of SAB (approximately 50% was a direct effect).【Conclusion】These results clarify the differences in soil boron nutrition status between northern and southern sericulture regions, pointing out the specific direction of soil boron regulation under the background of differentiated soil pH, and provide a theoretical basis for constructing a national-scale boron nutrition management system for mulberry orchards in China.