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The laser land leveling of turning radius is large and the twowheel support is easy to appear rim, which is not suitable for the accurate flat land of the small field. A multiwheel support laser land leveling hanging on tractor was designed. By analyzing the floating function of the threepoint suspension mechanism of the tractor and the multiwheel support, the working principle of the lasercontrolled flat shovel was realized. The mathematical model of the floating lifting shovel was established, and the structural parameters and working parameters of the grader were determined. Based on compaction analysis of the support wheel, the support wheel structure composing of two sets of rigid wheels was designed, which reduced the compaction and rim of the soft surface of the twowheel support. The field test of the prototype showed that the operation performance of the machine was stable. The maximum elevation difference and standard deviation of the field were reduced from 20.8cm and 4.48cm to 7.3cm and 1.72cm, respectively. The cumulative percentage of the sampling points with the absolute difference between the sampling point and the mean was less than 3cm was 9194%, which can significantly improve the smoothing of the field and meet the requirements of accurate flat land in the small field. The soil compaction degree of the grid points before and after the flat ground was compared and analyzed, which indicated that the compaction effect of the multiwheel support on the test field appeared at 0~17.5cm. However, when the depth was more than 17.5cm, the soil compaction was basically stable, and the surface soil of the whole field was compacted evenly. Moreover, the soft soil was moderately compacted after leveling, which reduced the sedimentation in the later stage of the soil and ensured the smoothness of the field. The percentage of an area that can not be leveled in the field corners of the traction leveler and hanging leveler was analyzed through the mapping method. The result showed that in the 100m×100m, 36.5m×36.5m and 25.8m×25.8m, the proportion of area that can not be leveled with traction leveler was 0.78%,，5.8% and 19.4%, respectively, while the hanging leveler was only 0.09%, 0.68% and 2.25%, respectively, which showed that the hanging leveler was more suitable for small field flats.