The invention discloses a threshing and redrying method for reducing the stem content in strips and a stemming tool, belonging to the technical field of threshing and redrying of tobacco industry. The stemming of the tobacco leaves with the water content of 16 to 17 percent is carried out under the conditions of the environmental temperature of 18 to 25 DEG C and the humidity of 60 to 70 percent; the size of a frameset of a threshing machine unit is adjusted to a larger grade, the rotation speed of a threshing roller of the threshing machine unit is reduced by 5 to 10 percent, the rotation speed of the threshing roller of other machine unit is reduced by 3 to 8 percent, and the air distribution air speed of the threshing machine unit is increased by 5 to 10 percent. The threshing and redrying method omits the conventional step of the first moisturizing, and the second moisturizing is carried out by direct feeding on a selection table. The water content of the tobacco leaves in a cold room is improved by 9.5 to 10.5 percent, and the temperature of the drying area I is lowered by 8 to 10 DEG C, thereby carrying out the low-temperature slow drying of the tobacco leaves. The method of the invention has practical measures, simpleness and easy operation, and the obtained technical effects are significant. The stem content in the strips which are produced by using the method of the invention is significantly reduced, and the branch stems with the diameter of more than 1.0mm are also greatly reduced.