Abstract:The Northeast black soil region of China is a vital commodity grain production base, yet soil horizons with constraints pose significant challenges to grain productivity and sustainable agricultural development, constituting a potential threat to the entire region's agricultural utilization. We systematically analyzed the types, characteristics, formation processes of soil constraint horizons, and the agricultural utilization issues they posed. Furthermore, we summarized current improvement measures for these soil horizons. Lastly, we outlined future research priorities, which primarily including: deepening the understanding and theoretical summarization of the developmental mechanisms, formation, and evolution processes of soil constraint horizons to provide a scientific basis for improving China's soil system classification, which holds profound significance in the fields of soil genesis and taxonomy; and establishing a quantitative classification and zoning system for soils in the black soil region based on regional characteristics, proposing targeted improvements and zoned utilization strategies to provide a scientific foundation for developing and refining improvement measures for soil constraint horizons in the Northeast black soil region.