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In order to adjust to the requirement of hill seeding for pneumatic centralized metering device for hybrid rice, a seed hill feeding device was designed to supply quantitative seeds. According to the mechanical and physical properties of rice seeds and agronomic requirement of hill seeding, the involutetype modelhole was introduced. The main structural parameters of the seed hill feeding device were determined and the mechanical models of seed filling and throwing processes were established. The effects of varieties of rice seeds, number of involutetype feeding unit and rotational speed on seed feeding and hillforming performance were carried out in bench test. The results showed that when the number of involutetype feeding unit was 3~8 and rotational speed was 10~40r/min, the seed quantity was increased with the increase of number of involutetype feeding unit and rotational speed. The range of seed quantity was 2392~17732 grains per minute. The variation coefficient of seed quantity was less than 10% for the rotational speed of 20~40r/min. The seed hill feeding device could be applied in different varieties of rice seeds, but the seed quantity was affected by the length and bulk density of rice seed. The seed quantity per hill was increased with the increase of number of involutetype feeding unit, and decreased with the decrease of rotational speed. The optimum rotational speed which resulted in the variation coefficient of seed quantity per hill less than 25.0% was 20~30r/min. The seed quantity per hill was 19~38 grains. The hill diameter was increased with the increase of number of involutetype feeding unit and rotational speed. The seed spacing was stable for different treatments. The field experiments indicated that the hill seeding could be realized by using the seed hill feeding device. The average seedlings and seed spacing were 3.07 seedlings per hill and 180.2mm, respectively, which met the agronomic requirements of rice directseeding. The results can provide basis for structural design of pneumatic centralized metering device and hill seeding for hybrid rice.