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Focusing on addressing the issues commonly found in existing seed metering devices, such as uneven seeding and inadequate hole forming when dealing with large sowing rates, a double-track ejection type rice precision direct seeding metering device was developed. Drawing from theoretical analysis, the key components were designed. Using the DEM-MBD coupling simulation technology, a range of spring force parameters and factors were obtained and the accuracy of the adjusting mechanism to meet the requirements of seeding was determined. It was evident that the performance of the seeder was decreased significantly after the rotation speed exceeded 35r/min. To investigate the effects of rotation speed, adjustment depth, and sphericity on the performance of the device, a bench orthogonal test was conducted. A regression prediction model of the device performance evaluation index was established. The test results showed that when the rotation speed of the seeding wheel was 23.06r/min, the depth of the hole was 8.99mm, and the sphericity of the rice seed was 52.7%, the qualified rate was 88.58%, the missed sowing rate was 4.43%, and the reseeding rate was 6.99%. To verify the working performance of the device and the accuracy of the optimized parameters, a field experiment was conducted. The results showed that the verification test results were consistent with the optimized results, and the error between them and the predicted results of the regression equation was less than 2%, thus confirming the feasibility of the experiment and the accuracy of the parameters. Under the optimum parameters, the qualified rate of hole diameter was 100%, the average hole diameter was 3.62cm, the coefficient of variation of hole diameter was 18.45%, the average hole distance was 22.98cm, and the coefficient of variation of hole distance was 8.43%, average number of holes was 11.08, and the coefficient of variation was 17.56%. The designed seed metering device had good seeding performance, high qualified rate of hole diameter and low coefficient of variation, indicating that the seed metering device had good hole forming performance.