||Natto is a traditional fermented food in Japan which is made by fermenting steamed soybeans with Bacillus subtilis. It is characterized by unique viscous material and flavor. Natto will produce a plenty of active components, including protein, linolenic acid, isoflavones, lecithin, vitamin B1、B2、E、K , calcium, zinc, magnesium, potassium, iron, etc. Natto has been proud to be a functional food, and full of physiological functions such as thrombolysis, diabetic prevention, prevent osteoporosis, inhibit hypertension, elimination carcinogen for the human body, regulate the physiology, and gastrointestinal protection. This study simulated the commercial production process and economic analysis of bacillus subtilis natto of 25 tons/year. The estimated production cost and selling price could leave the product against the commercial competitive of bacillus subtilis natto. The annuals return on investman is estimated as 27.91%. Therefore, the commercial production of red yeast rice is worth to further studies.