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In order to reduce the cutting force and energy of millet stem, the reciprocating cutting test bench was developed to carry out the single factor cutting tests in different harvesting dates, stem region, combination of cutter, cutting inclination angle, blade oblique angle, average cutting speed and stem feeding speed. The response tests were carried out for three factors: average cutting speed, cutting inclination angle and blade oblique angle based on the single factor tests. The results of single factor tests showed that the cutting stress and unit area cutting energy were decreased with the increase of moisture content during harvest period. The cutting stress and unit area cutting energy were decreased with the increase of stem height, and the cutting stress and unit area cutting energy of internodes were lower than those of nodes. The cutting stress and unit area cutting energy of double-support cutting form were lower than those of single-support cutting form. When the cutting inclination angle was 0°~20°, the cutting stress and unit area cutting energy was firstly decreased and then increased with the increase of cutting inclination angle. When the blade oblique angle was 0°~48°, the cutting stress was decreased with the increase of blade oblique angle, but the unit area cutting energy was decreased firstly and then increased. When the average cutting speed was 0.5~1.5m/s, the cutting stress and unit area cutting energy were decreased firstly and then changed steadily with the increase of average cutting speed. The stem feeding speed had no significant effect on the cutting mechanical properties of the millet stem. The results of the response test showed that the order of three factors affecting the cutting stress and unit area cutting energy were as follows: average cutting speed, blade oblique angle and cutting inclination angle. The optimal cutting parameters were the average cutting speed of 1.19m/s, the cutting inclination angle of 7.2°and the blade oblique angle of 36.4°. Under the optimal parameters combination, the cutting stress and unit area cutting energy were 2.88MPa and 22.38mJ/mm2, respectively, and the relative error between verification test value and predicted value was less than 3.5%. The comparative test showed that the cutting stress and unit area cutting energy were reduced by 6.6% and 3.9%, respectively, when the blade oblique angle was 36.4° compared with that was 30° (standard typeⅡmoving blade).