Abstract: Obtaining the stem appearance and tissue mechanical properties of tomato plants is an important basis for the design of automated pruning actuators.In this paper, the tomato variety "Jiali 14" was taken as the research object, and the natural morphological parameters of tomato stems were obtained through field measurement.Based on the MTS E43 electronic universal testing machine to measurement of stems mechanical properties, Obtaining mechanical properties parameters such as tomato stem extrusion, shearing and delamination fracture.According to the maximum static friction generated when different positive pressures are applied to the stem, Using the least squares method, Estimated the maximum static friction coefficients with four typical engineering materials such as stainless steel, PVC, hard rubber and silica gel; In order to achieve lateral branch of tomato plants safe clamping and reliable separation, combine with that critical force constraint of stem reliable separation and clamping crush, To determine the hardness and elastic modulus of tomato lateral branch clamping flexible material.This study can provide theoretical basis for tomatoautomatic pruning in protected agriculture and the design of key pruning robotexecutive components.