Abstract: Abstract: The technology of rice potted-seedlings, which adopts a new type of transplanter, is one of the feasible approaches to explore the new models of rice planting mechanization in China. Plastic pots in the rice potted-seedling tray, which are independent of each other, are used to cultivate strong seedlings with a complete nutrition clod wrapped around their root systems. And then the seedlings are transplanted without injury in the field with a certain line of planting distance. In recent years, the research and extension have fully proved the production demonstration effect around China. In order to promote the combination and application of agricultural machinery with its supporting agronomy technology, this paper attempted to ascertain the rulers of tillers and the appropriate seedlings per hole for high-yield cultivation of rice potted-seedlings in mechanical transplanting. Wuyunjing24 was selected as the experimental material to investigate tillers emerging, panicles formation, and yield characteristics under different seedlings per hole. The results indicated: the tillers from the 1st to 9th tilling positions of the main stem and the simultaneous secondary tillers, which were greatly influenced by the seedlings per hole, had emerged and formed panicles in certain proportion. It was beneficial for the emerging of the low tillers from 1st and 2nd tilling positions when there were 1 or 2 strains of plants per plastic hole during the seedling period. Accordingly, the high tillers from the 8th tilling position and secondary tillers got a higher level of tilling rate during the field period. The number of final panicles was mainly from tillers with wide source parts in the maturation stage. The middle tillers from the 3rd and 4th tilling positions were promoted under the condition of 3 or 4 seedlings per hole, with the final panicles mainly from the 5th to 7th tilling positions while also a little bit low and the secondary tillers. When the seedlings per hole increased to 5 or 6 seedlings, the tilling rate and productive tiller percentage of each leaf significantly declined, with the final panicles mainly counting on the main stem and the middle tillers. The tillers from the middle positions showed a higher productive tiller percentage, and the tillers were the main source of the final panicles and the tiller panicles. The harvest yield of 5 or 6 seedlings per hole was lower than that from 3 or 4 seedlings per hole, but was higher than that from 1 or 2 seedlings per hole. There was a positive correlation between the population base and the effective panicles, and a negative correlation between seedlings per hole and grain per panicle; panicles and grain per panicle were the fundamental factors in deciding the yield. The suitable population base of the normal japonica rice, Wuyunjing24, with a large fringe, was 3-4 strains of plants per plastic hole, 3-4 seedlings per hole, through analysis of the multiple regression function of seedlings per hole on yield and consistent with the harvest yield. The experiment indicated the rules of tillers emergence and panicles formation for rice potted-seedling in mechanical transplanting, which provided a theoretical basis for the density of sowing and planting of the farm equipment in field production. According to the tilling characteristics of rice potted-seedlings, management measures of manure and water should be studied, for giving full play to the middle tillers of main stem. Appropriate seedlings per hole is the premise of high-yield cultivation, which particularly increases the grain yield, not only the panicle numbers, the grain numbers, setting percentage, and the gain weights but also for more harmonious yield factors.