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In order to improve the working quality and reduce the consumption of the machine for straw returning, the structure and the working mechanism of the twin-roller cultivator for straw returning were discussed. Based on the soil bin test-bed, a laboratory test device was designed for the rotary tillage components. The result of the soil bin test verified that the twin-roller working model with well coverage performance and relatively lower consumption was feasible. The cultivator was developed and the filed test of maize straw returning was conducted. The result showed that the machine had a high working quality. The qualification rate of straw chopping, stubble breaking and vegetation coverage rate all reached up to 90%.