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The displacement of soil and straw is an important part of conservation tillage and straw returning to field. To analyze and compare the displacements, field experiments with downcut and upcut rotary tillage were conducted under rotational speeds of 180, 230, 280r/min. The aluminum block and colored straw were labeled and arranged in lines parallel to the rotor axial to measure soil and straw displacement. The original and final positions of soil and straw tracers were drawn in CAD, it is found that the shape of final positions was similar to the arrangement of rotary blades attached to the rotor. The comparison of soil surface morphology and displacements of soil and straw were done with downcut and upcut rotary tillage, and conclusions are drawn as follows: straw burial rate in the downcut rotary tillage was higher than that of upcut rotary tillage, but the soil breakage rate in upcut rotary tillage was higher. The distribution of soil tracers was uniform after tillage; lateral and longitudinal straws appear aggregation phenomenon after two kinds of tillage and downcut rotary tillage was more obvious. The displacements of soil and straw in upcut rotary tillage are better than those of downcut rotary tillage, the displacements in upcut rotary tillage decreased with increasing rotational speed while the displacements in downcut rotary tillage increased with increasing rotational speed. Based on these findings, the operation type, rotational speed and the shape of the arrangement of rotary blades could be adjusted to meet the different requirements in horticulture.