A lot of pickling liquid is produced in the production process of tuber mustard, it has high salt concentration and is rich in organic substances, the sewage treatment is expensive and difficult. The tuber mustard pickling liquid is used as the raw material in the soy sauce brewing production line. Through the technologies of double-effect concentrate, insulation fermentation and fermentation with spraying-extraction in the pond, it can produce 600 t first-grade soy sauce and consume more than 1000 t tuber mustard pickling liquid annually, the product tastes delicious and has the aroma of pickle. According to the characteristics of the process, the production line is divided into concentration unit, koji making and fermentation unit, precipitation and filtration unit and deployment sterilization unit. The production line makes full use of tuber mustard pickling liquid with reasonable process and advanced equipment.