Abstract: Soil denitrification is one of the important pathways of nitrogen (N) loss in agricultural production. The development of denitrification inhibitors capable of regulating soil denitrification is of great significance for reducing N loss in farmland and improving N fertilizer use efficiency. In recent years, researchers have discovered and extracted procyanidin, a type of biological denitrification inhibitors (BDI), which exerted a relatively stable inhibitory effect on denitrification and nitrous oxide (N₂O) emission reduction. Meanwhile, procyanidin showed potential in increasing soil available N (mainly nitrate N, NO₃⁻-N) content and enhancing crop yield, making them promising novel inhibitor materials for regulating N transformation in agricultural production. This article systematically summarized the research progress on the application of procyanidin in agriculture and proposed the "triple inhibitor synergistic control" theory, which regulated the migration and transformation of fertilizer N in soil through the combined application of urease inhibitors, nitrification inhibitors and denitrification inhibitors, achieving the goal of improving N fertilizer use efficiency, increasing crop yield and protecting the environment. The research results provided a new development direction for the green transformation of stabilized fertilizers in China.