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In order to solve problems of poor ridging effect and high traction resistance of existing sweet potato ridging shaping machine, a ploughshare furrowing ridging device of sweet potato ridging shaping machine was designed and its main structure and working principle were explained. According to the sweet potato planting pattern and ridging structure agronomic requirements, the structure parameters and value range of the plow body surface of the furrowing ridging device were determined by the horizontal straight element line method. The EDEM discrete element simulation software was used to establish interaction model of the ploughshare furrowing ridging device and soil. The installation angle, bulldozing angle and element line angle difference of the furrowing plow body surface were selected as the experiment factors, and the evaluation indexes were the soil throwing distance and traction resistance of the plow body, the Box-Behnken central composite design experiment was carried out. The simulation experiment results showed that the optimal combinations of the installation angle, bulldozing angle and element line angle difference were 27.19°, 38.05° and 10.69° when the operating speed of the sweet potato ridging shaping machine was 3.33km/h. Field experiment were carried out based on the optimal combination parameters. The ploughshare furrowing ridging device experiment results showed that the ridge height stability coefficient was 98.53%, the ridge soil firmness was 236 kPa, the fuel consumption of tractor operating was 11.94 L/h, which can meet the sweet potato furrowing ridging agronomic requirements. The operating effect of the ploughshare furrowing ridging device was better than that of the now existing plate type ridging device.