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Based on the objective reality of the sticky soil and large amount of straw in the rice-oil rotation area of the mid-lower Yangtze River, the traditional rotary tillage method for rapeseed direct seeding often leads to practical problems such as shallow plough layer, low stubble burying rate and low flatness. Combined with the agronomic requirements for the preparation of rapeseed seedbeds, a shovel-type seedbed preparation machine suitable for rapeseed direct seeding that realized the functions of soil plowing, soil crushing, straw burial covering, and leveling was designed, which cut and threw soil through active shovel, and integrated passive trenching, soil crushing, and flat surface. According to the requirements of the shovel entry angle, tillage depth, soil cutting pitch, etc., a kinematic model of the crank connecting rod mechanism was established. Based on the Matlab software analysis, the structure parameters of the crank connecting rod mechanism were obtained. And according to the requirements of shovel tip movement trajectory, cutting pitch, ditch bottom protrusion height, etc., the left and right staggered structure of the shovel and the crank spiral arrangement were determined. And the matching design of the unit operating parameters was carried out, the speed ( vm ) was 0.4~0.5m/s, the crank rotation speed (n) was 240r/min. The analysis of the movement process of the soil after being thrown by the shovel was carried out, the installation parameters of the enclosure were determined. A simulation model for the interaction of tillage components-soil-straw based on the discrete element method was established. The EDEM and ADAMS software were used to analyze the straw burial performance of the machine, and the simulation results showed that the average straw burial rate was 91.64%, which can realize the deep burying of straw and returning it to the field. Field experiments showed that under the condition of high stubble rice straw, the average working depth of the shovel-type seedbed preparation machine was 215.3mm, which was 99.2 mm higher than that of the traditional rotary tillage method; the stubble burying rate was 89.43%, which was an increase of 27.61 percentage points compared with the traditional rotary tillage method. The operation effect of the whole machine met the requirements for the preparation of the rapeseed direct seeding bed in the rice stubble field.