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Today, as global food security receives increasing attention, fertilizers play a crucial role as the cornerstone of modern agricultural production. The potassium content and biuret content in compound fertilizers are important indicators of product quality, as they directly affect the effectiveness of the fertilizer and the quality of agricultural products. As one of the three essential nutrients, potassium plays a crucial role in ensuring crop yields ； Biuret, on the other hand, is a common impurity in urea-based fertilizers; it can have an adverse effect on crop uptake and pose a threat to the ecological environment. With the development of the fertilizer industry and continuous improvements in testing methods, establishing more scientific and rapid standards for testing methods is crucial for the high-quality development of the compound fertilizer industry. \"Determination of potassium content in compound fertilizers\" (GB/T 8574-2024) specifies the methods for extracting and determining the potassium content in compound fertilizers. This standard employs ultrasonic extraction combined with ICP-OES to measure potassium content, a method that simplifies the procedural steps and prevents losses and cross-contamination during the analysis. As verified in the laboratory, the recovery rate of the potassium reference standard using this method is 99.33%. This method is convenient and fast, offers high accuracy and precision, and has broad applicability; it can significantly reduce the testing time, making it highly suitable for the batch analysis of large numbers of samples. \"Determination of biuret content in compound fertilizers\" (GB/T 22924-2024) specifies the test methods for determining the biuret content in compound fertilizers. The high-performance liquid chromatography method adopted in this revised standard addresses the issue of poor separation of nitrate ions and urea derivatives containing amide bonds, which occurred when C18 chromatography columns were used in the previous standard, thereby limiting the applicability of that standard. As verified by laboratory tests, this method shows a spiked recovery rate of 95.22%–107.24% for different concentration gradients in the samples, with a relative standard deviation (RSD) of 0.69%–2.72% for duplicate tests; it thus features high accuracy, high precision, and broad applicability.