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Aiming at the problem of large resistance of clay soil by subsoiling in midlower Yangtze River, based on the principle of sliding cutting and selfexcited vibration, a sliding cutting selfexcited vibration subsoiling device was designed. The sliding cutting angle and cutting edge angle of the sliding cutting shovel handle were analyzed and the parameters were designed. The finite element analysis showed that the strength of the shovel handle met the design requirements, and the internal and external double springs were designed to reduce the structural size of the selfexcited vibration device. The soil tank comparing test showed that, compared with the traditional arc subsoiling shovel, the fixed connection mode of sliding cutting subsoiling shovel reduced drag by 7.79%~8.81% at various speeds, and the selfexcited vibration connection mode of sliding cutting subsoiling shovel reduced drag by 15.45%~20.05% at various speeds. Field performance test showed that the soil firmness was decreased significantly at different depths after subsoiling, which was decreased by 78.18%, 56.08% and 62.72% at depths of 0～10cm, 10～20cm and 20～30cm, respectively. Soil bulk density was decreased by 14.66%~20.81% at different depths after subsoiling. Soil moisture content was decreased slightly at 0～10cm, and increased slightly at 10～20cm and 20～30cm. The average soil disturbance coefficient was 60.8% and the average soil bulkiness was 11.9%. The subsoiling depth and its stability coefficient conformed to the index. The working quality of sliding cutting selfexcited vibration subsoiling met the operation requirements as a whole. The research results can provide reference for the study of subsoiling drag reduction.