Validated analytical methods have been adopted in Codex Alimentarius Commission for international regulatory analysis. They also have been needed in the Japanese Agricultural Standard (JAS) because of increased international business through the import and export. In this regard, the Food and Agricultural Materials Inspection Center (FAMIC) have designed the candidate analytical methods and conducted their interlaboratory studies in commission of the Minister of Agriculture, Forestry and Fisheries. All procedures were performed under the international harmonized protocol of method-performance study. In this article, the general procedure for analytical methods in the JAS is summarized. Practical interlaboratory studies, performed at FAMIC, are also introduced on determination of crude protein and ash in macaroni products.