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In view of the problems such as large working resistance, small area of loose soil and poor surface flatness when the deep-loosening equipment is applied to banana field soil in tropical agricultural area of Hainan Province, a kind of the inclined handle folding wing subsoiling shovel was designed, which can effectively reduce working resistance based on the physical characteristics of latosoil in banana field soil of Hainan Province. The three-layer soil particle virtual simulation soil tank model was established by using the discrete element method, and the Hertz-Mindlin with JKR contact model was used to compare and simulate the operation performance of inclined handle folding wing subsoiling shovel and straight handle chisel subsoiling shovel. The results showed that on the premise of ensuring the subsoiling efficiency, the simulation test of the optimal operating speed of the subsoiling shovel was carried out, and the optimal operating speed range of the inclined handle folding wing subsoiling shovel was 3.24~3.96km/h;compared with the straight shank chisel subsoiling shovel, the working resistance of the inclined handle folding wing subsoiling shovel was reduced by 16.2%, the surface flatness was increased by 25.9%, and the groove width was reduced by 36.3%;the field test results showed that the error between the measured and simulated values of tillage resistance, surface flatness and subsoiling groove width of inclined handle folding wing subsoiling shovel and straight handle chisel subsoiling shovel was less than 2%, and the simulation results were highly reliable. The simulation analysis and field experiments showed that compared with the straight handle chisel subsoiling shovel, the inclined handle folding wing subsoiling shovel had less damage to the surface contour during operation, which can effectively reduce the disturbance to the soil layer and increase the loose soil area, and it had high surface flatness and small groove width after operation, so it can better adapt to the working environment of banana field in tropical agricultural area.