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Aiming to solve the problems of high working resistance and high energy consumption of soil touching parts of agricultural production equipment, a technical scheme of reducing resistance was proposed by using ultrasonic high frequency vibration assisted soil cutting excavation, and the ultrasonic vibration soil cutting and digging device was designed. 20kHz was selected as the excitation frequency, and the structural parameters of the key components such as sandwich transducer and conical horn were analyzed and designed based on the target of coupling resonance effect. The finite element model of the horn was established, and the modal analysis and harmonic response analysis were carried out by using the simulation method. The simulation results showed that the natural frequency of the horn axis expansion was close to 20kHz, which was consistent with the design value. The test platform of ultrasonic vibration soil excavation resistance was set up, and the soil trench test of cutting resistance of soil with and without ultrasonic vibration was carried out. The test results showed that compared with the rigid digging shovel without vibration, the ultrasonic vibration digging shovel can effectively reduce the soil digging resistance. Under the conditions of soil hardness of 1.5MPa, 2.5MPa and 3.5MPa, the corresponding soil digging resistance of ultrasonic vibration digging shovel can be effectively reduced. The resistance reduction rates were 35.1%, 40.7% and 44.3%, respectively. The greater the soil hardness was, the more obvious the drag reduction effect of ultrasonic vibration digging shovel was. With the increase of soil moisture content, the soil cutting resistance was decreased rapidly and then increased slowly. Due to the additional energy consumption of ultrasonic vibration excitation, the total energy consumption of vibration excavation was not effectively reduced. The experimental results verified the feasibility of the resistance reduction scheme and the rationality of the design parameters of the ultrasonic vibration soil cutting and digging device.