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Aiming at the problems of low weeding rate, easy damage to seedlings during operation of paddy field weeding devices in Northeast China, a curved-tooth oblique type inter-row weeding device was designed. Through the mechanical analysis of the buried ability of the wheel tooth entering the soil and the process of unearthed desorption during the operation of the weeding wheel, the corresponding mechanical model of the soil particles on the weeding wheel teeth was established, and the influence of the tooth structure on the operating performance was explored. The main structural parameters affected the weeding effect and the range of the parameters were determined through theoretical analysis, and a single-hinge structure profiling mechanism was designed. Combining with LS-DYNA simulation of display dynamics and rotating orthogonal experiment design, the optimal structure parameter combination of the curved-tooth oblique inter-row weeding wheel was obtained. The operation performance of the device was verified by field experiments. The research results showed that the weed burying effect and removal effect of the curved-tooth surface was better than that of the straight surface and the main structural parameters affected the performance of the curved-tooth oblique type inter-row weeding device were the curvature radius and the eccentricity of the weeding wheel. The simulation test showed that the optimal parameter combination was 65.86mm and 113.27mm, respectively. Field test results showed that the average weeding rate and average seedling damage rate of the device were 89.66% and 2.1%, respectively. The operation performance was stable, which can meet the agronomic and technical requirements of paddy field mechanical weeding operations.