The title of the thesis is the name of the Product Certification Institution, hereinafter referred to as Lspro, is an institution conducting SNI Mark Product User Certification activities by the Medan Industrial Research and Standardization Center. All this time, the Research Center and Medan Industrial Standardization for SNI Mark Product User Certification hereinafter referred to as SPPT - SNI is SNI Mark Product User Certification issued by the Product Certification Institute to producers who are able to produce goods produced in accordance with SNI requirements. However, the process of classifying the data possessed by the Medan Industrial Research and Standardization Center is too much so that when the certification data classification process is carried out it will take a very long time and will have an impact on granting such certification. C5.0 algorithm is an algorithm that produces a simpler decision tree and a more efficient use of memory. C5.0 algorithm can classify tree-based and rule-based prediction models. The use of C5.0 algorithm to get a decision model with a result of a higher level of accuracy This method will calculate faster. The purpose of this research is to be able to help speed up the decision making process, manage information contained in transaction data into new knowledge in SPPT-SNI by the Research and Standardization Center