Abstract: In order to improve scale planting and breeding technology of Lilium davidii var. unicolor under factory three-dimensional conditions, response of propagation effect of different layers of scale bulbs of Lilium davidii var. unicolor to addition of different substrates was studied, substrate type and scale level with more production and application value were selected, and it could provide scientific data support for demonstration and promotion of factory three-dimensional scale breeding technology of Lilium davidii var. unicolor．Results showed that suspected incidence rate of vermiculite treated scales was the lowest, suspected incidence rate of vermiculite treated scales increased rapidly from 25 to 50 days, and suspected incidence rate of vermiculite treated scales decreased slowly from 50 to 75 days．Suspected incidence rate of outer scales was the highest, and suspected incidence rate of inner scales was the lowest．When treated with vermiculite for 75 days, differentiation rate of middle layer scales reached the highest of 93.23%, and differentiation rate of middle and inner layer scales was higher than that of outer layer．The highest differentiation number of small bulbs in middle layer of scale was 2.21 per piece, and there was a small difference in number of small bulbs differentiated between inner and middle layers of scale．Average fresh weight of a single scale bulb treated with vermiculite was 0.68 g, average number of roots was 0.77, number of fruiting bulbs per scale was 4.03, proportion of bulbs with a circumference greater than 2 cm was 60.33%, and reproduction coefficient was 2.68．