The invention relates to a preparation process of a nutritional bamboo salt. At present, the preparation process of the nutritional bamboo salt, which is simple in production process and high in salt nutritional value and can effectively prevent the bamboo salt from being polluted by heavy metal, is not available. The process comprises the following steps of: selecting fresh bamboos, and cutting the bamboos into bamboo tubes; adding salt into the bamboo tubes, wherein the salt accounts for 4/5 relative to the height of each bamboo tube; adding bamboo leaves into the bamboo tubes, wherein the bamboo leaves account for 1/5 relative to the height of each bamboo tube; then compacting the salt and the bamboo salt; baking the bamboo tubes for 6-10 hours at 900-1100 DEG C, and naturally cooling;taking out the salt from the cooled bamboo tubes, and crushing; adding the crushed salt and the bamboo leaves into the bamboo tubes, sealing the bamboo tubes with yellow mud; placing the bamboo tubesinto a fire-resistant tank with a cover to isolate air, baking for 3-8 hours at 150-300 DEG C, and cooling; and taking out the salt in the cooled bamboo tubes, and crushing the salt to obtain the nutritional bamboo salt. The preparation process disclosed by the invention is simple, the nutritional value of the salt is high, and the bamboo salt can be effectively prevented from being polluted by the heavy metal.