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Aiming at the problem of continuous cropping obstacles that seriously restrict the sustainable development of Panax notoginseng planting, a needle steam output device was designed. The structural parameters of the disinfection needle were optimized and verified by the soilbin test. The simulation experiments of the needle’s internal were carried out by Fluent software, the test results showed that the flow rate and pressure of the disinfection needle were increased, and no significant change in outlet temperature was found. The basic law of soil heating was verified by the soilbin test. The soil can be heated to 90℃ in 5 minutes, and the heating efficiency of the lower soil was low, and that of the upper soil was high. In order to explore the effect of different structural parameters of the disinfecting needle on the warming effect of the soil, the number, diameter and steam emission angle of the hole on one side were selected as the test factors of the soilbin test, and the time required for the soil to rise to 90℃ was selected as the test index, and orthogonal tests were carried out respectively to determine the optimal structural parameters of the disinfecting needle. When the number of single side orifices was 4, the diameter of the orifice was 2mm, and the steam exit angle was 45°, the heating time of soil by the disinfection needle structure was the shortest, for 116s. The optimal arrangement of disinfection needles was 6×6 layout, the optimal number was 36, and the spacing was 250mm by the heat transfer simulation of Fluent porous media. The changes in soil organic matter and pH value after disinfection were tested, the soil environment after disinfection met the environmental requirements for the growth of Panax notoginseng.