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The hand-held shaking branch jujube harvester was designed to solve the problems of low manual harvesting efficiency and difficulty of large-scale mechanical harvesting in the process of jujube harvesting. By establishing the “fruit-branch” single pendulum dynamic model of jujube, the conditions of fruit shedding under forced vibration were analyzed, the dynamic model was solved, the main influencing factors affecting the picking effect of jujube were determined as vibration frequency, amplitude and clamping position. The free modal response and harmonic response analysis of the jujube plant model were carried out by ANSYS simulation software. The results showed that when the vibration frequency was 4~12 Hz, the amplitude was 10~20 mm, and the clamping position was 0.3~0.7, the displacement of the main branch and the hanging fruit branch was obvious and there was less damage to the tree. In order to determine the optimal working parameters of the picking device, the three-factor and three-level vibration picking test was carried out with the picking rate of jujube as the evaluation index. Mathematical regression model of picking jujube and the influencing factors were obtained. The experimental data and response surface were analyzed and optimized by Design-Expert software. The optimal working parameters were determined as follows: the vibration frequency was 5.91 Hz, the amplitude was 15.30 mm, the clamping position was 0.45. At this time, the picking rate of jujube was 93.33%. It can be seen through the validation test that the picking rate of jujube was 94.18%, which was similar to tlee optimized values, indicating that the optimized model was reliable.