Abstract: Nitrogen fertilizer is a fundamental input for global food production, yet its average use efficiency is below 50%. Significant nitrogen losses through ammonia volatilization, nitrification-denitrification, and leaching contribute to greenhouse gas emissions, water pollution, and ecological degradation, posing severe environmental challenges. Consequently, developing synergistic technologies to enhance nitrogen use efficiency has become an urgent priority for sustainable agricultural transformation. Urease inhibitors and nitrification inhibitors, by precisely regulating key microbial processes in soil nitrogen transformation, effectively reduce nitrogen losses at the source and serve as the technological cornerstone for environmentally friendly stabilized fertilizers. This review provides a comprehensive synthesis of the mechanisms, historical development, technological innovations, and field applications of these two inhibitor classes, establishing for the first time an integrated logical framework spanning "fundamental mechanisms—technological innovation—product design—application validation." It not only elucidates the molecular and microbial-level action mechanisms of inhibitors and traces the paradigm shift from conventional chemical inhibitors to green bio-sourced inhibitors but also highlights the product systems of stabilized fertilizers based on inhibitor combinations, intelligent formulation technologies, and integration with biostimulants, along with empirical evidence of their yield-enhancing and efficiency-increasing effects in major cropping systems. This review aims to offer a systematic knowledge base and forward-looking perspective for academic research, product development, and large-scale application in related fields, providing crucial theoretical reference and practical strategies for promoting fertilizer reduction and efficiency enhancement, controlling agricultural non-point source pollution, and achieving carbon neutrality goals in China.