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Aiming at the problem that the existing gripper hill-seeder in Xinjiang is easy to hole, and the seed filling performance needs to be further improved, a kind of combination-hole maize precision dibbler metering device was designed combining with the characteristics of wheel hole hill-seeder and stepped hole with strong adaptability to seeds, through theoretical analysis, the relative movement model between the combined-hole and the seed wheel was established, and the influence rule of its relative position on seed filling process was analyzed, and the parameters and range that affected seeding performance was determined, and the parameters of the combined-hole and the truss plate were designed. The single factor test was carried out to determine and narrow the scope of key parameters. The direction angle of hole, location angle of hole and rotating speed of metering device were taken as experimental factors, and taking the qualified index of seed spacing, multiple index and missing index as the test evaluations for three factors and three levels Box-Behnken central combination tests, and the mathematical model between experimental factors and indexes was got. Design-Expert software was used to optimize the regression model. The optimum parameters were as follows: the hole depth was 12.3mm, the direction angle of hole was 20.3°, the location angle of hole was 44.7°, the rotating speed of metering device was 40r/min. At this time, the qualified index of seeding was 89.12%, the multiple index was 7.30%, and the missing index was 3.87%. In the optimal parameter combination test, the qualified, the multiple and missing index were 91.14%, 4.23% and 4.63%, respectively. The result of soil bin test showed that the forward speed of seeder was 3.38km/h, the qualified index for seeding was 92.53%, the multiple index was 3.54%, and the missing index was 3.93%, The qualified index of seeding was increased by 2.53 percentage points compared with the clamping dibbler.