Aerial bulbil, other than axillary branch and tendril, is a special propagative organ in Lilium lancifolium, but the development events occurring during bulbil formation of L. lancifolium have not been reported. In this study, we observed the changes of morphology and anatomical structure during the process of bulbil formation in L. lancifolium. The results indicated that bulbils of L. lancifolium formed in the joint region of leaf and stem and were derived from the division and diferentiation of axillary meristem cells. Bulbils frst generated on a certain leaf axil in the upper portion of stem, and then formed upward along the upper stem. The present study provides histological information for further studying the mechanism of bulbil formation.