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Under the background of conservation tillage, the advantages of less tillage and no-tillage cultivation techniques, such as water storage and soil conservation, have been emphasized. In order to solve the shortcomings of full tillage, a belt tillage machine was designed for seedbed preparation, and its key components were studied. According to the existing wide and narrow planting row spacing of rice, belt land preparation with 30cm bandwidth was realized by selecting rotary blade and designing blade arrangement. Meanwhile, no-tillage operation was carried out in the adjacent 30cm area to realize the purpose of fine land preparation between paddy beds. After one operation, seedling transplanting could be carried out in the water field. The orthogonal rotation test method was used to simulate the actual field operation through EDEM discrete element simulation, and the optimal arrangement of strip rotary blades was obtained. At this time, the simulation results were as follows: the soil crushing rate was 93.26%, and the surface flatness was 17.3mm. On this basis, field experiments were carried out, and the results showed that the soil crushing rate, surface flatness, single tillage bandwidth, and tillage bandwidth stability of multi-functional combined tillage machine were 92.97%, 18.4mm, 300.9mm, 95.3%, respectively. The stability of tillage depth, shallow subsoil depth, tillage depth and deep subsoil depth were 151.3mm, 221.4mm, 93.5% and 92.3%, respectively, which fully met the needs of largescale rice seedbed soil preparation. The research was focused on determining the structural parameters of strip rotary tillage, ensuring the stability of tillage bandwidth and good operation results. It provided reference for the design and research of less and no-tillage equipment for paddy field.