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The nitrogen, phosphorus, and potassium contents are the key factors to determine the quality of organic fertilizers and right amount of application for agricultural uses. The major nutrient contents in raw materials used for making organic fertilizers and products were evaluated in this study. Among the raw materials that were investigated, soybean cake gave the highest total N content at 76 g kg^-1, followed by perilla cake (70 g kg^-1), rape seed oil cake (66 g kg^-1), cotton seed cake (54 g kg^-1), and rice bran (22 g kg^-1). We investigated 43organic fertilizers and our results showed widely varied concentrations of major nutrients : total N at 30.5-139g kg^-1, total P_2O_5 at 2.3-96.3 g kg^-1, and total K_2O at 0.1-29.3 g kg^-1. Our study would like to emphasize the importance of nutrient content labeling in packed organic fertilizers to be able to know its efficiency and for determining the right amount for application.