The invention discloses a processing process of dregs containing chromium. The processing process includes the steps of a, preparing blast furnace slag and gypsum into a cementing material or preparing blast furnace slag and anhydrous Na2SO4 into a cementing material, wherein the adding amount of the gypsum is 5-15% of the mass of the cementing material or the adding amount of the anhydrous Na2SO4 is 0.5-10% of the mass of the cementing material; b, mixing the dregs containing chromium with the cementing material and alkaline clear liquid, and evenly stirring to obtain mortar containing chromium, and maintaining the mortar containing chromium to obtain a jet-grouted solid, wherein the mass ratio of the cementing material to the dregs containing chromium is (1:0.5)-(1:6), and the mass ratio of the alkaline clear liquid to the cementing material is 0.3-0.5. The processing process has the advantages that the blast furnace slag and the gypsum or the blast furnace slag and the anhydrous Na2SO4 are used as the raw materials to prepare the cementing material according to a certain proportion, the cementing material can effectively cement the dregs, containing chromium, generated in the process of wastewater treatment and is good in stabilizing effect on hexavalent chromium, and secondary harm, caused by the dregs containing chromium, on environments is avoided.