The invention relates to a method for increasing the retention rate of calcium carbonate in paper-process reconstituted tobacco sheets. The purpose of the invention is to solve the problems that: since the prior art directly adds calcium carbonate, the bonding force between the calcium carbonate and tobacco fibers is weak, as a result, loss is severe, the material utilization rate is low, the amount of waste water to be treated is large, and the treatment cost is high. The technical point is that: needed chemical constituents are extracted from tobacco material, residue is ground into pulp after extraction, and the concentration of the pulp is regulated between 3 percent and 25 percent; the solution of soluble carbonate accounting for 4 percent to 40 percent of the weight of dry fibers in the pulp is added into the pulp, and is fully stirred and uniformly mixed, and impregnation is then carried out for 20 to 150 minutes, so that the fibers of the pulp can be impregnated with the soluble carbonate; the solution of soluble calcium salt, the molar mass of which is approximately equal to the molar mass of the soluble carbonate, is added into the impregnated pulp, and is fully stirred and uniformly mixed, static reaction is then carried out for 30 to 180 minutes, and the reaction temperature is controlled at 5 DEG C to 50 DEG C; and after the static reaction, the pulp is made into reconstituted tobacco sheets by papermaking equipment.