The invention relates to the technical field of food processing, particularly to a brassica juncea production process, which comprises: selecting brassica juncea harvested on the day, and washing; cutting the brassica juncea into flakes; placing 100 kg of the cutting brassica juncea into a jar; saucing, wherein jar flipping is performed 4 times every day during 1-3 days of saucing, jar flipping is performed 3 times every day during 4-6 days of saucing, jar flipping is performed 2 times every day during 7-15 days of saucing, jar flipping is performed one time every day during 16-20 days of saucing, and brine is required to be completely removed during every jar flipping; selecting the weather with a temperature of 30-35 DEG C and having continuous 3-4 sunny days, and filling granular powder, a matching material and the saruced brassica juncea into an urn under sunlight shielding, wherein a layer of the granular powder is spreaded after a layer of the sauced brassica juncea is paved, then a layer of the matching material is paved, and the steps are repeatedly performed; and maintaining the temperature at 20-25 DEG C, and fermenting for 10 days. The brassica juncea produced through the brassica juncea production process has characteristics of delicious taste, rich nutrition and persistent flavor. In addition, industrial production can be achieved, the processing technology is simple, the technology is easy to achieve, and the labor intensity is low.