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Due to the differences of soil, climate, varieties in different regions and different planting habits, the rice planting agronomic requirements are different. In order to meet the seeding requirement of conventional rice and hybrid rice simultaneously and to adjust the seeding rate quickly, a combined holetype metering device was designed based on a simple holetype metering device which was developed by South China Agricultural University. The device included holetype shell, holetype roller and adjusting mechanism. A complete holetype was comprised by the label through holes which were uniformly distributed on the holetype shell and the small/big holetype which were uniformly distributed on holetype roller. The shape, size and style of the holetype and the adjusting mechanism were designed and optimized. The reliability experiments of the adjusting mechanism were carried out and the result showed that its structure was reasonable and the seeding rate adjusting process could be completed in 5 s. According to the existed model and theory, the outline dimensions of the holetype were calculated and the results confirmed that the number of the holetype was 8, the big radius was 5mm, the small radius was 4.5mm and the length was 11mm. To further study on the main impact factors of the seeding performance of the metering device, the length and the chamfering angle of the guiding groove and the type of the holetype were selected as the factors of the performance experiment while the conventional rice pregerminated seed Yuxiangyouzhan was selected as the experimental material. The results indicated that the optimal combination parameters were the length of the guiding groove of 6.5mm, the chamfering angle of 60°, the big holetype on the holetype roller with 6.5mm cylindrical hole and the small holetype with 4mm spoonshaped hole. The test results with rotational speed of 50r/min showed that the qualified rate of the seed number per hole of the small holetype was 87%, the seeding qualified rate of the big holetype was 8767%, and the seeding variable coefficients of these towed holetype were 2260% and 2046% which could meet the rice seeding requirement. The correlation analysis showed that the main effect on the qualified rate was the type of the holetype, and the length and the chamfering angle of the guiding groove had effects on the seeding variable coefficients as well. Furthermore, the adaptability experiment was designed by 4 varieties pregerminated rice seeds and 4 rotational speeds (30r/min, 40r/min, 50r/min and 60r/min). The results showed that the combined holetype metering device had good adaptability of seeding conventional rice seeds such as Xiushui 134 and Yuxiangyouzhan, and hybrid rice seeds such as Huayou 14 and Peizataifeng.