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The common problem in fertilization in rural areas of our country at present is excessive application of nitrogen fertilizer along with low utilization rates; the average national utilization rate of nitrogen during the growing season is less than 30%, and in some areas it is only 16%–22%, whereas the global utilization rate of nitrogen is over 50%. According to experts, the annual loss of nitrogen fertilizers in our country is equivalent to 24 million tons of urea, which is worth 36 billion yuan in RMB terms. Not only are the benefits reduced, but it also pollutes the soil and water sources, causing harm to the environment on which people depend for survival. Therefore, improving the utilization rate of nitrogen fertilizers is not only related to the direct interests of farmers but also to food safety and environmental quality. The main pathways of nitrogen fertilizer loss are ammonia volatilization, nitrate leaching, and denitrification. To improve the utilization rate of nitrogen fertilizers, efforts should be focused on the following aspects: First, widely adopt deep application of nitrogen fertilizers – this is a fertilization technique that has been identified by the Ministry of Science and Technology and the Ministry of Agriculture as one worthy of widespread promotion. Deep application of nitrogen fertilizers refers mainly to applying ammonium nitrogen fertilizers, urea, and other nitrogen fertilizers, including nitrogen-containing compound (mixed) fertilizers, at a depth of 10–15 centimeters, followed by timely covering with soil. The utilization rate of fertilizers can be increased by 10–15%. II. The combined application of nitrogen fertilizers with other fertilizers mainly includes the combination of nitrogen fertilizers with organic fertilizers as well as phosphorus and potassium fertilizers; it is important to achieve a balanced application of synthetic nitrogen, phosphorus, and potassium fertilizers, as well as to combine nitrogen fertilizers with organic fertilizers. The combination of nitrogen fertilizers and organic fertilizers has a significant effect on improving soil quality and increasing yields, while also enhancing the utilization rate of nitrogen ； The balanced application of nitrogen, phosphorus, and potassium has significant synergistic effects. Various nitrogen-containing compound fertilizers and specialty fertilizers take into full account the requirements of balanced fertilization, resulting in often good application effects and high utilization rates. III. Application of large-grained urea, and the widespread use of a mixture of urea and phosphate fertilizers; large-grained urea is a compound of urea and formaldehyde ； When urea and phosphate fertilizers are applied to the soil together, they can also form a complex of urea and phosphate fertilizers. Both approaches can significantly slow down the conversion of urea nitrogen into ammonium nitrogen, thereby reducing ammonia volatilization and the losses associated with nitrification. Therefore, large-grained urea and compound fertilizers produced using urea, especially large-grained urea, as the nitrogen source and phosphate fertilizers as the phosphorus source are all fertilizer types that improve the utilization efficiency of nitrogen fertilizers. IV. Application of slow-release fertilizers, controlled-release fertilizers, and nitrogen fertilizer enhancers: Nitrogen fertilizer enhancers can be mixed at a rate of 2% of the pure nitrogen content, and used as base fertilizers or topdresses. They effectively inhibit the nitrification of ammonium nitrogen in the soil, reducing the loss of nitrate nitrogen as well as further denitrification. It consistently increases yields by about 10% in cereal crops such as rice, wheat, and corn, as well as in cotton.