Abstract: In order to explore the influence of open grape stalk on mechanical cutting force, the compressive elastic modulus and compressive strength of grape stalk in pruning period were measured by mechanical properties test, and the shear strength of grape branch fracture was determined to be 5.0-9.0 MPa. The geometric model of cutter and grape stalk was established for dynamic simulation, and the cutting process of reciprocating cutter was analyzed by using finite element analysis software ANSYS/LS-DYNA, and the displacement cloud map, equivalent stress cloud map, energy curve and cutting force curve of grape stalk pruning were obtained. On this basis, three factors and three levels of simulation experiments were carried out, and the effects of cutting device working parameters on cutting force from large to small were sorted as follows: cutting Angle, hydraulic motor speed, traveling speed, and the optimal combination of cutting device parameters was obtained by using Design-Expert12.0 software optimization analysis: The cutting angle was 9°, the hydraulic motor speed was 700 r/min, and the traveling speed was 1.5 m/s. Field experiments were carried out by using the optimal combination of parameters. The results showed that the rate of missing and tearing of reciprocating grape stem cutting device was 5.4% and 4.6%, and the optimal operating parameters of grape stem cutting device could meet the requirements of grape stem pruning.