Aiming at the problems of large surface straw coverage after mechanical harvesting of corn and returning straw to the field and surface soil mixed with straw after rotary tillage and the impact on subsequent seeding quality, combining the planting patterns and agronomic requirements of the wheat and maize for double cropping area in Huang-Huai-Hai region, a telescopic finger stalk burying device was designed based on commonly used rotary tillers. The device was mainly composed of a rotary tiller roller, a fence and a stalk tooth equipped with an eccentric telescopic finger set. The eccentric telescopic finger group first contacted the straw and then threw the straw close at a low speed. After the rotary cutter touched the soil that was cleared of the straw and threw the soil far at high speed and covered the straw, then the separate burial “the straw was under the soil” was achieved. The theoretical analysis of the motion of rotary tiller and telescopic finger in the straw burial device determined the relationship between the speed of the rotary tiller. Besides, the telescopic finger and the structure and parameter design of key components such as the eccentric telescopic finger group, the fence and the stalk teeth were completed. By using the multibody dynamics RecurDyn software to track the motion trajectories of the end points of rotary cultivator, telescopic finger and pressing stalk teeth and analyze the speed and angular velocity motion rules of the three end points, it was found that the motion laws were consistent with the theoretical analysis. Field comparison tests were performed on the straw burial device and the conventional rotary cultivating device, and the straw burial rate of the surface below 50 mm was measured. The results showed that the burial rate of the straw burial device was 83.25%, which was 10.05 percentage points higher than that of the conventional rotary cultivating device. 