At present, there are two main methods for measuring creatinine enzyme. One is to monitor the enzyme kinetics of creatinine aminohydrolase coupled with glutamate dehydrogenase, and the other is to measure the enzyme kinetics of creatinine aminohydrolase coupled with creatine oxidase and peroxidase in the Trinder reaction. Among them, the latter, due to the relatively low price of reagents, is not affected by blood ammonia and other interfering substances, and currently has a large supply of commercial reagent kits. Enzymatic determination of serum creatinine has high specificity, minimal interference factors, higher accuracy and precision, and is more suitable for automatic analysis. The creatinase creatine oxidase method introduced in this article for the determination of serum creatinine effectively eliminates the interference of endogenous creatine and vitamin C on various enzymatic reactions due to the use of dual reagents and the addition of ascorbic acid oxidase in the reagents. The addition of substances such as potassium ferrocyanide to the reagent can enhance the anti bilirubin interference ability of this method, further improving the accuracy of the determination results. In addition, due to its simple operation, relatively low reagent price, good precision, wide linear range, mild reaction conditions, and applicability to automated analysis, this method is a good method worth recommending.